Western Slope Skies - May 27th Black Holes: Truth or Myth?
Did you know, regardless of how close we are, you’ll never actually be able to see a black hole? We can only observe the effect of a black hole. Typically, black holes are the remnants of a star that died in a supernova. In 1958, David Finklestein published the interpretation of a black hole as a region of space from which nothing can escape (not even light). Before then, black holes were a “mathematical curiosity”, so it was not until the 1960s when theoretical work showed they were a prediction of general relativity. Soon after that the first black holes were recognized by light emitted from the hot region where companion stars were ripped apart. The closest black holes are stellar-mass black holes a few thousand light years away from Earth. There is also a supermassive black hole approximately 28 thousand lightyears away at the center of our Milky Way Galaxy. In January 2020 researchers observed the collision between a black hole and a neutron star. What makes this more fascinating is a similar collision was observed ten days later.
Let’s play a game of truth or myth:
Black holes can be used to travel forward in time
- TRUE. Actually, you do not need a black hole to travel forward in time, just a region of space where gravity is strong. It sounds like science fiction, but this is a real effect that we observe on Earth. Time runs a little bit slower for us on Earth than it does in space. This is called gravitational time dilation. The only challenging part is actually getting to a black hole. You could approach a black hole, but not too close, and then fire your rockets to try to escape its gravitational pull. If you do escape, you’d return to the future. How cool would that be?
All black holes are black
- MYTH. Light can still be emitted from the region outside the event horizon, the point of no return. As matter gets closer to the black hole, it will begin to spin into a disk and heat up, causing it to shine brightly, so brightly that it emits X-Rays. NASA’s Chandra X-Ray Observatory has detected this X-Ray emission.
Black holes suck everything around them in
- MYTH. Black holes act like any other objects with mass. If the sun were to turn into a black hole, the Earth would continue orbiting it and not get sucked in.
All stars become black holes when they die
- MYTH. Usually smaller stars (like our sun) will become white dwarfs, while much larger stars will typically become either black holes or neutron stars.
Black holes may always be a mystery to people on Earth, but every day we come closer to finding new answers to the many questions we hold.
Western Slope Skies is produced by members of the Black Canyon Astronomical Society and KVNF Community Radio. This feature was written and recorded by Sora Lenz, an astronomy student of Dr. Catherine Whiting at Colorado Mesa University.