Ever wonder what a black hole looks like?
Chances are you haven’t, but it’s something astronomers and astrophysicists have puzzled over for a century.
On April 10, a working group of eight observatories around the world released the first-ever image of a black hole. It isn’t just an exciting piece of astronomy, it’s an important example of scientists and observatories around the world working together.
The Dominion Radio Astrophysical Observatory, near Penticton, wasn’t one of the participating observatories, but that doesn’t mean that astronomer Ken Tapping is any less excited about seeing a black hole.
“It’s a nice piece is a nice piece of research. A nice piece of very hard work to make this go,” said Tapping.
A black hole is a region of space from which nothing, not even light, can escape; their immense gravity continues to suck in matter for the hole to absorb. Tapping said the astronomy community, in one way or another, has been studying the “black hole issue” for a long time.
“Black holes are at the centre of many galaxies, including ours, and we know that particularly violent star explosions can compress the cores of stars to the point where they might make a small black hole,” he said.
The one that was observed is a particularly “beefy” one, according to Tapping, who said it’s in a galaxy (M87) that has been recognized as “strange” for a long time.
“It has a strong radio source and it has been known since about the 1950s,” said Tapping. “And a big jet of material coming out so we knew there was something very high energy happening in the middle of that galaxy, which is what made it a particularly good target for this.”
The M87 black hole is huge, estimated at 40 billion kilometres across, and has a mass 6.5 billion times that of our sun.
Black holes were postulated in Albert Einstein’s theories, but the image released on April 10 is the first direct evidence he was right.
“Everything observational about black holes to this point has been indirect. There is something small, driving huge amounts of energy and with a very, very large mass. When you plug those into the equations, the equations say this has to be a black hole. But this is the first time that anyone has actually imaged it,” said Tapping. “Even though what we see is living up to what we expected, there is still a tremendous amount we don’t know about black holes, we don’t really know what’s going on inside at all.“
Tapping said he doesn’t know whether creating an image of a black hole is going to be important for anybody other than an astrophysicist.
“The nearest big black hole that we know about at the centre of the galaxy, and it’s not going to be around here anytime soon,” said Tapping. “But the fact that we are getting together, combining technologies, working around the world swapping ideas, and looking at things and seeing the world in ways we have never seen before, I think that is really, really important.”
There are spin-offs from astronomy that have improved everyday life, Tapping explained. Developments in radio astronomy led to designs that made satellite TV possible, and the imaging techniques used for MRI scans were developed by radio astronomers.
“There are all sorts of things that radio astronomy has contributed or astronomy has contributed. But I don’t think that’s the key thing. The key thing is that as a species we are naturally curious,” said Tapping. “When you look at something like the discovery, this black hole, and you see scientists all over the world excited about it, this is bringing people together. This is something we as a community can be really proud of, and I think that’s great.”