black holes

Question 1

What powerful force allows black holes to absorb light?

Answer 1

Gravity

Question 2

How do scientists know that black holes exist?

Answer 2

By observing objects and light around black holes

Question 3

How do black holes form?

Answer 3

When giant stars explode

Question 4

Where do super massive black holes likely exist?

Answer 4

At the center of galaxies

Question 5

True or False: Black holes are invisible because they don’t reflect light.

Answer 5

TRUE

Question 6

What do we call the boundary around a black hole where nothing can escape its gravity?

Answer 6

Event horizon

Question 7

What is the center of a black hole called?

Answer 7

Singularity

Question 8

What is it called when an aging star explodes?

Answer 8

Supernova

Question 9

True or False: Black holes were first discovered by Ancient Egyptian astronomers around 3000 BCE.

Answer 9

FALSE

Question 10

What makes the gravity of a black hole so strong?

Answer 10

Its small size and large mass

Question 11

The Event Horizon Telescope captured the now-iconic image of the M87 black hole. Why is it called that?

1. It is at the centre of the galaxy Messier 87, named after astronomer Charles Messier
2. Its mass is roughly 87 solar masses
   
   3. It spins at 87 rotations per microsecond
   4. It is 87 million light years from Earth
   5. No one knows for sure

Answer 11

It is at the centre of the galaxy Messier 87, named after astronomer Charles Messier

Question 12

How many times more massive than our Sun is the M87 black hole?

Answer 12

6 billion times

Question 13

How far away from Earth is the M87 black hole?

Answer 13

55 million light years

Question 14

The Event Horizon Telescope required multiple telescopes, with split-second synchronization, to capture the image of the M87 black hole. How many telescopes were used?

Answer 14

Eight

Question 15

What quantity of stuff falls inexorably past the event horizon of the M87 black hole, never to be seen again, during the span of a single day?

Answer 15

The equivalent of 90 Earths

Question 16

The M87 black hole is supermassive, but relatively compact for its mass. What size does it occupy?

Answer 16

It is roughly the size of our solar system

Question 17

Over time, a black hole will evaporate via a process called Hawking radiation. How long will it take for the M87 black hole to fully evaporate?

Answer 17

Much longer than the current age of the universe

Question 18

If the black hole image captured by the Event Horizon Telescope had been egg-shaped instead of round, what could it mean?

Answer 18

That Einstein was wrong about general relativity

Question 19

Roughly how small would you have to squish the Earth for it to become a black hole?

Answer 19

The size of a wedding ring

Question 20

About how long will it take for our Sun to turn into a black hole?

Answer 20

It won’t – it’s too small

Question 21

If photons (light) have no mass, how can they be trapped by the gravitational field of a black hole?

Answer 21

Mass is actually linked to space, and the density of a black hole curves the space around it to an extreme degree