What exactly is a black hole?
A black hole is actually a region of space-time where gravity is so extreme that not even electromagnetic radiation like light can escape from it. It’s similar to the universe’s “holes” – they’re simply areas where the fabric of space-time becomes so distorted that what we perceive as reality (through our telescope, etc.) appears as “nothing” floating around in that region. Astronomy has actually found black holes by using very sensitive equipment to detect radiation coming from inside these holes.
Although astronomers have observed black holes with telescopes for many years, it wasn’t until March 2021 that scientists saw something really strange while looking at a piece of space debris. Using an instrument called a Very Expanding Universe Explorer (VEO) at NASA’s Herschel Space Center in Europe, scientists noticed something that seemed to be “hiding” in one of our galaxy’s event horizons. Yes, it was a black hole. What is a black hole and what are some of the effects that cause them to affect the space around them?
When a black hole starts to absorb matter, it spirals inward. This spiraling gets faster as it gets closer to a black hole’s event horizon – the point at which nothing, not even light, can escape. Once the black hole’s event horizon is reached, the spiral collapses and ejects matter into space. One theory is that black holes emit radio waves, x-rays, and gamma rays – and by spotting these emitted waves, researchers were able to determine that this is what caused the “aging” of distant stars.
Although astronomers have discovered black holes in the past, they weren’t able to pinpoint exactly what was causing their emission of radiation. Only over the past few decades have experts been able to study this type of radiation, and therefore infer different characteristics about black holes based on their presence. One way that they do this is by studying very faint X-rays that come from very close by galaxies. By detecting the amount of radiation emitted by matter falling toward or away from these black holes, astronomers can pin-point a variety of different processes that are going on.
If you thought that this was all that there was to black holes, then you would be greatly mistaken. Because black holes also play a major role in the formation of irregular galaxies, they can help astronomers study the properties of these very rare formations. By observing how black holes and their event horizons differ from the main events in the universe, scientists have gained a better understanding of how these building blocks of the universe work. They have also determined how they affect the development of other elements, such as hydrogen.
Although there is much to learn about black holes, it is still unknown what exactly they are and what they contribute to the structure of the entire universe. Astronomers have learned that they have an effect on very heavy and very light objects, as well as gas and dust in space. They also play a significant role in the distribution of gas in the gas clouds surrounding our planet. Knowing all of this just goes to show that understanding black holes is very important.