The Universe, Galaxies, and Stars: Review

Front

What does the HR diagram classify stars based on?

Back

The HR diagram classifies stars based on their surface temperature and absolute brightness (luminosity).

Front

How does the surface temperature of main sequence stars change?

Back

The surface temperature of main sequence stars increases as the absolute brightness increases.

Front

Which type of electromagnetic radiation is primarily used to observe heat emitted by objects in space?

Back

Infrared radiation is primarily used to observe the heat emitted by objects in space.

Front

What are the components of the electromagnetic (EM) spectrum?

Back

The components of the EM spectrum include visible light, X-rays, and gamma rays.

Front

What type of star can result in a black hole after its death?

Back

A black hole could be the result of the death of a high-mass star.

Front

What is absolute brightness (luminosity)?

Back

Absolute brightness (luminosity) is the total amount of energy emitted by a star per unit of time.

Front

What is the relationship between a star's diameter and its brightness?

Back

Generally, a star's absolute brightness increases with its diameter.

Front

What is the significance of the main sequence in the HR diagram?

Back

The main sequence is where stars spend most of their life cycle, fusing hydrogen into helium.

Front

What is a black hole?

Back

A black hole is a region in space where the gravitational pull is so strong that nothing, not even light, can escape from it.

Front

What is the role of infrared radiation in astronomy?

Back

Infrared radiation helps astronomers observe cooler objects in space, such as dust clouds and distant galaxies.