What is the difference between apparent and absolute magnitude of a star?

The apparent magnitude and absolute magnitude of a star are both measures of its brightness, but they refer to different things:

1. Apparent Magnitude:
   • This measures how bright a star appears from Earth.
   • It depends on both the star’s intrinsic brightness (how much light it emits) and its distance from Earth.
   • The lower the apparent magnitude, the brighter the star appears (a star with a negative apparent magnitude is brighter than one with a positive magnitude).
   • Example: The Sun has an apparent magnitude of -26.7, which is extremely bright when viewed from Earth.
2. Absolute Magnitude:
   • This measures how bright a star would appear if it were located 10 parsecs (about 32.6 light years) away from Earth.
   • It gives a measure of the star’s intrinsic brightness, independent of its distance from us.
   • A star’s absolute magnitude allows astronomers to compare the true luminosity of stars.
   • The lower the absolute magnitude, the more luminous the star.