Computed · lunar series

The Moon

Every phase and every apsis for the year ahead, computed from the same lunar series behind the Moon pages. The phases are checked on every build against NASA's own published table; the apsides have no comparable published table to check against, and their cards say so.

Times are UTC throughout, because an instant is the same everywhere and a local rendering would hide which day an event actually falls on for you. Nothing here knows or asks where you are. Every computed instant carries an uncertainty, and most of those are measurements rather than estimates: every build checks the lunar phases against NASA's own published table, the equinoxes, solstices and Earth's apsides against the US Naval Observatory's, and the planetary positions the remaining events are derived from against JPL Horizons. The Moon's perigee and apogee are the one family with no external table to check against, and their cards say so.

77 events

First Quarter Moon
Computed
18 September 2026, 20:47 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
19 September 2026, about 06:03 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 404,200 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Full Moon
Computed
26 September 2026, 16:55 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
1 October 2026, about 19:54 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 369,300 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Last Quarter Moon
Computed
3 October 2026, 13:28 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
New Moon
Computed
10 October 2026, 15:50 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
17 October 2026, about 01:37 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 404,400 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
First Quarter Moon
Computed
18 October 2026, 16:23 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Full Moon
Computed
26 October 2026, 04:37 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
28 October 2026, about 20:45 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 364,400 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Last Quarter Moon
Computed
1 November 2026, 20:45 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
New Moon
Computed
9 November 2026, 07:05 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
13 November 2026, about 18:40 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 405,300 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
First Quarter Moon
Computed
17 November 2026, 11:56 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Full Moon
Computed
24 November 2026, 15:24 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
25 November 2026, about 23:40 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 359,500 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Last Quarter Moon
Computed
1 December 2026, 06:35 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
New Moon
Computed
9 December 2026, 00:55 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
11 December 2026, about 06:05 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 406,300 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
First Quarter Moon
Computed
17 December 2026, 05:37 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Full Moon
Computed
24 December 2026, 01:44 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
24 December 2026, about 09:31 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 357,000 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Last Quarter Moon
Computed
30 December 2026, 19:23 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
7 January 2027, about 09:25 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 406,600 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
New Moon
Computed
7 January 2027, 20:25 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
First Quarter Moon
Computed
15 January 2027, 20:15 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
21 January 2027, about 20:44 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 357,500 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Full Moon
Computed
22 January 2027, 12:07 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Last Quarter Moon
Computed
29 January 2027, 11:04 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
3 February 2027, about 15:12 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 406,100 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
New Moon
Computed
6 February 2027, 15:57 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
First Quarter Moon
Computed
14 February 2027, 07:38 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
19 February 2027, about 05:04 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 361,000 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Full Moon
Computed
20 February 2027, 22:56 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Last Quarter Moon
Computed
28 February 2027, 05:08 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
3 March 2027, about 05:03 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 405,000 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
New Moon
Computed
8 March 2027, 09:31 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
First Quarter Moon
Computed
15 March 2027, 16:18 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
19 March 2027, about 02:57 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 366,200 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Full Moon
Computed
22 March 2027, 10:23 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Last Quarter Moon
Computed
30 March 2027, 00:40 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
30 March 2027, about 23:12 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 404,200 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
New Moon
Computed
6 April 2027, 23:54 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
First Quarter Moon
Computed
13 April 2027, 23:03 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
14 April 2027, about 02:35 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 370,100 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Full Moon
Computed
20 April 2027, 22:31 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
27 April 2027, about 19:08 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 404,400 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Last Quarter Moon
Computed
28 April 2027, 20:20 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
New Moon
Computed
6 May 2027, 11:03 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
9 May 2027, about 17:40 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 366,600 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
First Quarter Moon
Computed
13 May 2027, 04:53 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Full Moon
Computed
20 May 2027, 11:24 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
25 May 2027, about 14:47 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 405,100 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Last Quarter Moon
Computed
28 May 2027, 14:24 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
New Moon
Computed
4 June 2027, 19:49 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
6 June 2027, about 13:46 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 361,500 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
First Quarter Moon
Computed
11 June 2027, 10:55 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Full Moon
Computed
19 June 2027, 01:07 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
22 June 2027, about 06:36 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 405,900 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Last Quarter Moon
Computed
27 June 2027, 05:31 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
New Moon
Computed
4 July 2027, 03:14 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
4 July 2027, about 21:01 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 358,000 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
First Quarter Moon
Computed
10 July 2027, 18:25 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Full Moon
Computed
18 July 2027, 15:46 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
19 July 2027, about 12:27 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 406,300 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Last Quarter Moon
Computed
26 July 2027, 17:22 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
2 August 2027, about 07:23 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 357,100 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
New Moon
Computed
2 August 2027, 10:16 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
First Quarter Moon
Computed
9 August 2027, 04:33 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
15 August 2027, about 13:11 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 406,300 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Full Moon
Computed
17 August 2027, 07:05 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Last Quarter Moon
Computed
25 August 2027, 02:34 UTC
Half the disc is lit again, on the other side. The Moon rises around midnight, so the evening sky is dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at perigee
Computed
30 August 2027, about 17:12 UTC
The Moon reaches the closest point of its orbit this month, appearing marginally larger than average — a difference of a few per cent in diameter, not something the eye registers without a side-by-side comparison.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 359,000 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
New Moon
Computed
31 August 2027, 17:46 UTC
The Moon passes between Earth and the Sun and its near side is unlit. The darkest skies of the month fall around this date.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
First Quarter Moon
Computed
7 September 2027, 18:14 UTC
Half the Moon's disc is lit. It stands highest in the early evening and sets around midnight, leaving the second half of the night dark.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.
Moon at apogee
Computed
12 September 2027, about 00:24 UTC
The Moon reaches the farthest point of its orbit this month and appears marginally smaller than average.
How exact: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Distance
about 405,700 km, centre to centre
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: A turning point of the Earth–Moon distance from the low-precision lunar series, located by bisecting the derivative after a coarse scan. (lunar-apsis-distance-extremum, version 1.0.0)
Uncertainty: The date is reliable; the hour is not. The distance curve is almost flat for a day either side, and unlike the phases and the equinoxes this one is not checked against an external table — no comparable published series is connected — so treat the time as indicative.
Where it applies: A property of the orbit, the same for every observer.
Full Moon
Computed
15 September 2027, 22:34 UTC
The Moon is opposite the Sun and fully lit, above the horizon all night. Faint objects are washed out for several nights either side.
How exact: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where this date comes from
Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Method: The instant the Moon's geocentric ecliptic longitude exceeds the Sun's by the phase angle, both referred to the mean equinox of date, located by bisection on the low-precision lunar and solar series. (lunar-phase-elongation-crossing, version 1.0.0)
Uncertainty: Within about forty minutes of NASA’s published instant — measured, not asserted: the build checks every phase of 2026–2028 against NASA’s own table and the largest disagreement is thirty-eight minutes. The limit is the truncated lunar theory the whole platform uses, not the search.
Where it applies: The instant is the same everywhere; only the local clock time and whether the Moon is above your horizon differ.

Four kinds of date

Computed: Derived on this platform from published position series. The algorithm and its version are recorded, and the stated uncertainty is the real one.
Published prediction: Taken from an authority's own published prediction. AsteriaStar reproduces it and links the document; it does not recompute it.
Annual forecast: Recurs every year at approximately the same point in Earth's orbit. The date shown is the expected one; the exact hour and the strength vary from year to year.
Planned: A date somebody intends to meet. Planned dates move, often by months. The timestamp of the last confirmation is shown so you can judge how much the date is worth.

Take this away as a calendar file: subscribe or download the next year of events, or read it as JSON from the Open Data API. Both carry the basis, the method or source, and the uncertainty for every entry.

The Moon

77 events

First Quarter Moon

Moon at apogee

Full Moon

Moon at perigee

Last Quarter Moon

New Moon

Moon at apogee

First Quarter Moon

Full Moon

Moon at perigee

Last Quarter Moon

New Moon

Moon at apogee

First Quarter Moon

Full Moon

Moon at perigee

Last Quarter Moon

New Moon

Moon at apogee

First Quarter Moon

Full Moon

Moon at perigee

Last Quarter Moon

Moon at apogee

New Moon

First Quarter Moon

Moon at perigee

Full Moon

Last Quarter Moon

Moon at apogee

New Moon

First Quarter Moon

Moon at perigee

Full Moon

Last Quarter Moon

Moon at apogee

New Moon

First Quarter Moon

Moon at perigee

Full Moon

Last Quarter Moon

Moon at apogee

New Moon

First Quarter Moon

Moon at perigee

Full Moon

Moon at apogee

Last Quarter Moon

New Moon

Moon at perigee

First Quarter Moon

Full Moon

Moon at apogee

Last Quarter Moon

New Moon

Moon at perigee

First Quarter Moon

Full Moon

Moon at apogee

Last Quarter Moon

New Moon

Moon at perigee

First Quarter Moon

Full Moon

Moon at apogee

Last Quarter Moon

Moon at perigee

New Moon

First Quarter Moon

Moon at apogee

Full Moon

Last Quarter Moon

Moon at perigee

New Moon

First Quarter Moon

Moon at apogee

Full Moon

Four kinds of date