CH 22 HW

Why is it difficult for astronomers to detect black holes?

Black holes reside in a region of space that is dark, empty, and undetectable by any astronomical instruments.

What characteristic of black holes makes them hard to observe?

Their escape speed is greater than the speed of light.

What are the fastest spinning pulsars associated with?

They spin fastest.

Where does the X-ray emission from a neutron star in a binary system primarily come from?

Heated material in an accretion disk around the neutron star.

Gamma-ray bursts are observed to occur approximately uniformly over what?

The entire sky.

What property of neutron stars is important in explaining how pulsars generate radiation?

Neutron stars can rotate extremely rapidly, as quickly as 30 times a second or more.

If the Sun were to turn into a black hole of the same mass, what would happen to Earth's orbit?

Earth's orbit would remain unchanged.

Neutron stars and pulsars are associated with what event in stellar evolution?

The collapse and supernova explosion of massive stars.

What does the term 'black holes' refer to?

They prevent anything inside the event horizon from escaping.

What causes the X-ray radiation observed in a binary system with a blue supergiant star and a black hole?

The accretion disk of material falling into the black hole.

What provides the best evidence for supermassive black holes in the centers of galaxies?

Rapid gas motion and intense energy emission.

What contributes to a neutron star's immense gravitational attraction?

Its large mass.