The gravitational field of a black hole is so strong that _______ can escape from its event horizon.
Only a spacecraft with very powerful engines
Nothing, not even the light
Only electrons
Astronomers can observe black holes because.
The volume of space inside the event horizon emits light
They observe the gravitational effects of the black holes on the space around them
They are connected with space-time tunnels to Earth
Where are black holes typically located?
Super-massive black holes sit at the center of the galaxy
Outside galaxies, in the intergalactic space
Inside galaxies, but there are none in the Milky Way
It is _______ that planet Earth will be destroyed by a black hole.
Impossible
Certain
Possible, but extremely unlikely
Black holes are fundamental components of the universe because.
They contributed to the formation and evolution of galaxies
They get rid of useless stars and planets
They are amusing objects for astronomers