Oh No, I'm Trapped in a Black Hole Quiz

Answer: an area of space-time where nothing that is sucked in can escape

A black hole is a place in space where the gravitational pull is so strong that nothing can escape from it, not even light. The gravitational pull of Earth is strong enough that when the space shuttle is launched, it needs to reach a certain speed, or velocity, in order to break free of the Earth's orbit and enter space; this is called the escape velocity.

The speed required to accomplish this is approximately seven miles a second, which translates to 420 miles a minute, or 25,200 miles per hour (which is pretty darned fast).

The gravitational pull of a black hole is believed to be so high that nothing, not even light (traveling at 186,000 miles per second), can escape. (I know that it's impossible, for any one of a dozen good reasons, for my kid to be keeping one of these things in his room - but let's just pretend for a while.)

Answer: from the explosion of a large star

Scientists believe that black holes are created when a large star, and I mean a really large star, undergoes a Supernova explosion. After the explosion, the matter (or material that made up the star) that is left collapses into itself (or implodes) because of its own gravity, becoming a neutron star. Neutron stars are very dense and as they continue to collapse in on themselves and shrink, their mass becomes even denser. Finally they reach a point where their gravitational pull is so strong that it does not let anything escape, and a black hole is formed.

Answer: by having its mass compressed

When the mass of an object becomes compressed, the gravitational pull that the mass exerted remains constant, but becomes compressed, or concentrated, into a much smaller object. This means that even though it remains constant, it becomes more powerful.

I know that this is confusing, so let's try another way. Take the gravitational pull of the Earth. It's strong enough to keep us from falling off but weak enough that we are able to move around. If we are able get a rocket ship moving fast enough, we can blast out of the gravitational pull and into space.
Now, take the Earth and compress it into the size of a marble (which is about the size that the Earth would have to be compressed to in order to create a black hole). Remember, we aren't changing the mass of the Earth at all, just squishing it so that it's really, really tight, or dense. That mass would exert the same gravitational pull, but because it's now compressed into a really small area, it would be incredibly powerful. With black holes (and no, the Earth could never become one) we're talking about objects with considerably more mass. So much so that when they are compressed in the same way, they are still very large.

Answer: No

Black holes are not as powerful as all that. While anything that gets close enough to be pulled into the gravitational pull is a goner, there is plenty of area outside of that danger zone that is safe. Scientists refer to the area of no escape as the horizon, or the event horizon.

As long as you stay away from the event horizon you, and anything else around you, should be safe, which explains why my kid hasn't fallen in yet. He must know where the event horizon is.

Answer: You don't... you have to study the objects around them.

Very little light can escape the gravitational pull of a black hole, so it is difficult to detect them by the light coming from within. If an area of large mass, that emits very little light, is located, then it's a pretty good guess that a black hole has been found. You can sometimes see the light from the material being sucked into it (so to speak).

When gases are being pulled into a black hole they often get very hot, due to the friction, and the x-ray and radio waves that they emit in this heated state are easy to measure. So the true detection of a black hole really comes from the measurement of the objects around it.

In 2017 scientists were first able to photograph a black hole 50 million light years from Earth, using the Event Horizon Telescope.

Answer: No one knows for certain.

Since nothing is believed to escape the gravitational pull of a black hole, scientists can only speculate on what you would see if you were ever unfortunate enough to fall in there. It is generally believed that you would be able to see the light from the objects still outside of the black hole, but whether or not there would be any light within is anybody's guess. Scientists do believe that all of the matter inside the black hole is piled up in the centre in a single point, often referred to as the singularity.

They believe that anyone unfortunate enough to fall into a black hole (presumably in a space craft of some description or you'd be dead from lack of air) would be drawn towards this singularity, feeling the increasing pull of the gravity as they get closer, until they were literally crushed, becoming part of the singularity.

Answer: anywhere from six miles across, to the size of our solar system

While it is theoretically possible for a black hole to be any size, it is unlikely that they would ever (naturally) be any smaller than six miles across. This is because of the size of sun that is needed to undergo a supernova explosion, and start the path towards becoming a black hole. Scientists have found a supermassive black hole (approximately the size of our solar system) at the centre of the Milky Way. Supermassive black holes have also been found at the centre of other galaxies, leading scientists to speculation that there is one of these at the centre of every galaxy. Supermassive black holes are much larger (in every way) than normal stellar black holes, and there have been a few theories as to how they have become so large. One popular theory is that these supermassive black holes started out as regular stellar black holes, and that they have grown (by incorporating gases and other stars).

A second theory discusses the possibility of two or more black holes merging to form a larger (w)hole (pun intended).

Answer: No

Aside from the obvious differences in size, some black holes actually spin on an axis. The event horizons for these black holes are actually two spheres around the singularities, which are believed to be thin rings instead of single points. The matter in space just outside of the event horizons is dragged around with the rotation, in a whirlpool-like effect.

This has led scientists to posit the theory that there is an area around the black hole and outside of the event horizon, which they have called the ergosphere. If you happened into ergosphere you would also be dragged into the rotational movement, but you could still escape the gravitational pull and not necessarily end up inside the black hole.

Answer: billions

Of course not every black hole has been discovered, but given the number that have been discovered and applying that to the vastness of space, it is believed that there are literally billions in existence, with more being created all the time. It was once believed that because a black hole allows nothing to escape, it would last forever.

However Stephen Hawking developed a theory (by applying quantum field theory) that posits that they do indeed evaporate and shrink over time. According to quantum theory, there are tiny particles of light, on a sub-atomic level, that are managing to escape from a black hole all the time.

Some of the glow seen around the event horizon, which had previously been thought to be created entirely by the heating of the gasses being drawn into the black hole, could possibly be evidence of this light escaping. Based on this theory, some of the mass from the singularity of the black hole would be released back into the universe, causing the hole to diminish, albeit negligibly, but over time this could add up.

Answer: No

Stars that experience supernova explosions, and end up becoming black holes tend to be considerably larger than our sun...10 to 15 times larger in mass, actually. That amount of mass is needed in order to leave enough residue after the explosion, to produce the density required for a black hole to develop.