Front

What is a large system of billions of stars called?

Back

A galaxy.

Front

Why can't we see stars during the daytime?

Back

Because the light from the sun blocks them.

Front

What is the best explanation for why Alpha Centauri A appears less bright than the Sun despite being larger?

Back

Alpha Centauri A is further away from Earth than the Sun.

Front

Why does the Sun appear brighter than other stars in the sky?

Back

Because it is nearer to Earth.

Front

What measurement do we use to measure distances to a star?

Back

Light Year.

Front

What is the definition of apparent brightness?

Back

Apparent brightness is the brightness of a star as seen from Earth, which depends on its distance and intrinsic luminosity.

Front

What is the difference between apparent brightness and absolute brightness?

Back

Apparent brightness is how bright a star appears from Earth, while absolute brightness is the intrinsic brightness of a star at a standard distance of 10 parsecs.

Front

What factors affect the apparent brightness of a star?

Back

The distance to the star and its intrinsic luminosity.

Front

What is luminosity in the context of stars?

Back

Luminosity is the total amount of energy emitted by a star per unit of time.

Front

How does distance affect the apparent brightness of a star?

Back

As the distance from a star increases, its apparent brightness decreases.