Black hole- Hard

What did the Event Horizon Telescope release on April 10th, 2019?

• Results of a space mission

• First-ever image of a black hole

• New scientific theory

• Image of a distant galaxy

What does the sphere in the mock black hole represent?

• The event horizon

• The singularity

• The photon sphere

• The accretion disk

What is the location from which not even light fired radially away from the black hole could be detected by an outside observer?

• The accretion disk

• The event horizon

• The singularity

• The photon sphere

What is the radius of the event horizon known as?

• The Schwarzschild radius

• The Photon radius

• The Singularity radius

• The Accretion radius

What is the resulting shadow of the black hole in the image?

• 3 times the size of the event horizon

• 2.5 times the size of the event horizon

• 2 times the size of the event horizon

• 2.6 times the size of the event horizon

What do we actually see in the image of a black hole?

• All of the above

• The photon sphere

• The event horizon

• The inner most stable circular orbit

What determines the brightness of one side of the accretion disk compared to the other?

• The distance of the accretion disk from the black hole

• The direction of the accretion disk

• The speed of the accretion disk

• The temperature of the accretion disk

What effect causes one side of the accretion disk to look much brighter than the other?

• Gravitational lensing

• Doppler effect

• Time dilation

• Relativistic beaming

What do light rays coming off the accretion disk do due to the black hole warping space-time?

• They form a ring around the black hole

• They get absorbed by the black hole

• They escape to infinity

• They bend over the top and end up coming to our telescopes

What do light rays coming off the bottom of the accretion disk do due to the black hole warping space-time?

• They bend over the top and end up coming to our telescopes

• They get absorbed by the black hole

• They form a ring around the black hole

• They escape to infinity