Alkalurops B
51 Boötis
Scientific overview
Alkalurops B is a yellow dwarf in the constellation Boötes (Boötis), lying about 117.62 light-years from Earth.
Class G. Yellow stars like the Sun. On the main sequence they steadily fuse hydrogen into helium. Such stars have surface temperatures around 5,200–6,000 K and appear yellow to the eye.
Physical properties
| Spectral type | G1V |
| Luminosity class | V |
| Apparent magnitude | 6.51 |
| Absolute magnitude | 3.73 |
| Luminosity (Sun = 1) | 2.818 |
| Colour index (B−V) | 0.6 |
| Distance | 117.62 ly (36.06 pc) |
Values are real catalogue data; fields without a reliable value are omitted, never estimated.
Precision measurements
Astrometry and astrophysics from SIMBAD and Gaia DR3 · Gaia DR3 1387349065967311744
| Parallax | 27.73 ± 0.65 mas | SIMBAD · measured |
| Distance | 36.6992 pc | Gaia · estimated |
| Proper motion (RA) | -140.1 mas/yr | SIMBAD · measured |
| Proper motion (Dec) | 84.78 mas/yr | SIMBAD · measured |
| Radial velocity | -8.5 ± 0.3 km/s | SIMBAD · measured |
| Spectral type | G0V | SIMBAD · catalogued |
| Effective temperature | 5988 K | Gaia · modeled |
| Radius | 1.2337 R_sun | Gaia · modeled |
| Surface gravity (log g) | 4.2054 log(cm/s^2) | Gaia · modeled |
| Metallicity [M/H] | -0.3475 dex | Gaia · modeled |
| Right ascension (ICRS) | 231.1 deg | SIMBAD · measured |
| Declination (ICRS) | 37.3473 deg | SIMBAD · measured |
Full field-level provenance
- Parallax: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · plx_value · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
- Distance: ESA Gaia astrometric survey · Gaia EDR3 · Bailer-Jones (2021) · external.gaiaedr3_distance · r_med_geo · row 1387349065967311744 · Bayesian estimate · retrieved 2026-07-11
- Proper motion (RA): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · pmra · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
- Proper motion (Dec): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · pmdec · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
- Radial velocity: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · rvz_radvel · 2006AstL...32..759G · direct catalogue measurement · retrieved 2026-07-11
- Spectral type: Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · sp_type · 1981ApJS...45..437A · catalogue identifier/value · retrieved 2026-07-11
- Effective temperature: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · teff_gspphot · row 1387349065967311744 · model output · retrieved 2026-07-11
- Radius: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · radius_gspphot · row 1387349065967311744 · model output · retrieved 2026-07-11
- Surface gravity (log g): ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · logg_gspphot · row 1387349065967311744 · model output · retrieved 2026-07-11
- Metallicity [M/H]: ESA Gaia astrometric survey · Gaia DR3 · gaiadr3.astrophysical_parameters · mh_gspphot · row 1387349065967311744 · model output · retrieved 2026-07-11
- Right ascension (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · ra · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
- Declination (ICRS): Centre de données astronomiques de Strasbourg (CDS) · SIMBAD · basic · dec · 2007A&A...474..653V · direct catalogue measurement · retrieved 2026-07-11
measured = direct catalogue value · estimated = Bayesian inference (Bailer-Jones distance) · modeled = model output (Gaia GSP-Phot). Fields a source did not provide are omitted, never invented.
Evolution
A yellow dwarf is a G-type main-sequence star like the Sun. After about ten billion years it will swell into a red giant and finally leave behind a white dwarf.
Location in the sky
Knowledge connections
- In constellationBoötes
Related stars in Boötes
Sources
The primary and reference sources this topic draws on.
- HYG DatabaseHYG Database (Hipparcos + Yale Bright Star + Gliese), by D. Nash / astronexus
Aggregated, openly-licensed star catalogue combining Hipparcos, the Yale Bright Star Catalogue, and the Gliese Catalogue of Nearby Stars.
- HipparcosESA Hipparcos space astrometry mission
High-precision parallax, magnitude, and position for ~118,000 stars.