Photometry & distance · μ = 5 log₁₀(d) − 5
Distance Modulus
The difference between apparent and absolute magnitude, which encodes distance. A modulus of five corresponds to 100 parsecs; each five magnitudes multiply the distance tenfold.
Distance modulus5mag
Formula: μ = 5 log₁₀(d) − 5
Worked example
With the default inputs, distance modulus evaluates to 5 mag — 100 pc → μ = 5. The validator recomputes this against the known value on every build, so the formula is checked, not asserted.
Highlights
- ›100 pc → μ = 5
The physics behind it
Knowledge connections
- Associated withParallax
Sources
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.