EVERYDAY SCIENCE

Detailed explanation-1: -Absolute brightness, also known as absolute magnitude, is different from both luminosity and apparent brightness. Absolute brightness is the apparent brightness of a star if it were viewed at a standard distance of ten parsecs, or 32.6 light years, away from Earth.

Detailed explanation-2: -Astronomers define star brightness in terms of apparent magnitude-how bright the star appears from Earth-and absolute magnitude-how bright the star appears at a standard distance of 32.6 light-years, or 10 parsecs.

Detailed explanation-3: -Absolute magnitude is the “true” brightness of a star if it were at a standard distance of about 32.6 light-years. The difference between the two magnitudes is directly related to a star’s distance. Color is a manifestation of a star’s temperature.

Detailed explanation-4: -Astronomers compare the true brightness of stars by calculating how they would look if viewed from a standard distance of 32.6 light years away. If the Sun were viewed from this distance it would appear over 300 times fainter than Sirius (the brightest star in our nighttime sky) appears to us on Earth.