Properties of Stars Review Flashcard

Front

What is absolute magnitude?

Back

Absolute magnitude is a measure of the intrinsic brightness of a star, defined as the brightness a star would have if it were located 10 parsecs away from Earth.

Front

What is luminosity?

Back

Luminosity is the total amount of energy emitted by a star per unit of time, often expressed in watts.

Front

What is apparent magnitude?

Back

Apparent magnitude is a measure of how bright a star appears from Earth, which can be affected by distance and interstellar dust.

Front

How does distance affect the apparent brightness of a star?

Back

The farther away a star is, the dimmer it appears to an observer on Earth, even if its intrinsic brightness (luminosity) is high.

Front

What is the difference between absolute magnitude and apparent magnitude?

Back

Absolute magnitude measures a star's true brightness at a standard distance, while apparent magnitude measures how bright the star appears from Earth.

Front

What is a light-year?

Back

A light-year is the distance that light travels in one year, approximately 5.88 trillion miles (9.46 trillion kilometers).

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What is the main reason stars appear smaller than the Sun?

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Stars appear smaller than the Sun primarily because they are much farther away from Earth.

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What is a dwarf star?

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A dwarf star is a small and relatively low-luminosity star, which can include red dwarfs and white dwarfs.

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What is the significance of a star's size in relation to its luminosity?

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Generally, larger stars are more luminous than smaller stars, but this is not always the case as temperature and composition also play a role.

Front

What is the relationship between luminosity and distance for two stars with the same apparent magnitude?

Back

If two stars have the same apparent magnitude, the one that is farther away must be more luminous to appear equally bright.