Which of the following would be considered an Emission Nebula?

Stars spend 90% of their lifetime

The absolute magnitude of a star is defined to be the apparent magnitude that the star would have if it were at a standard distance of _____ parsec(s).

What is the likely final fate of a star whose mass is 25 solar masses after it has finished its nuclear burning phases?

What would happen to the Earth if the sun suddenly became a black hole? (ignore the temperature change)

Which of the following can be used as standard candles for determining distance?

During star formation, the dense parts of the molecular cloud that collect material while contracting and heating up are known as

Which of these layers of the Sun is coolest?

List the Spectral types in order of temperature from Hottest to Coolest.

Which of the following would be considered a Reflection Nebula?