Suppose it were possible to lower a yellow sodium lamp toward the event horizon of a black hole. What would an observer see while watching from a safe distance?

Which of these mechanisms is NOT a common way in which star formation is triggered or started?

Apparent magnitude is a measure of a star’s

As one moves upward and to the left on the H-R diagram, the stars become

At what stage of its evolutionary life is the Sun?

What prevents a neutron star from collapsing and becoming a black hole?

Why do astronomers seek to measure gravitational waves simultaneously with at least three detectors?

Where are the MOST massive stars to be found in the main sequence of a Hertzsprung–Russell diagram?

A star of apparent magnitude +2.1 appears _____ than a star of apparent magnitude –1.2.

In the spectral classification scheme, what designation is given to a star just a little cooler than a K5 star?