Most of us probably think we know what a black hole looks like. If you search the internet for black hole, lots of cosmic images will show up. However, the truth is, that’s all speculation. No human has ever seen a black hole. Taking an image of a black hole is also nearly impossible. Why? Glad you asked.
Wait, What Is A Black Hole Again?
Where There Is No Light, There Is No Seeing (At Least Not Yet)
Because a black hole absorbs all light, meaning it is unable to both emit and reflect light, it is virtually impossible to see it. We can’t see things without light, which means we can’t see a black hole. That does not stop us from trying though. Enter the Event Horizon Telescope. This is a telescope that was designed to show us what it looks like around a black hole. The goal isn’t actually to get a direct image of the black hole, though this definitely seems like a step in the right direction.
The Event Horizon Telescope is not just one telescope, but between 15 and 20 radio telescopes that all point at the same thing. This amounts to a telescope the size of Earth with the power to see an ant crawling along the surface of the moon. Remember that black holes are not gigantic, but infinitely small points.
That’s another reason why they are so hard to see, and why we need such a large telescope to even have a chance of catching a glimpse. Also, factor in that the closest black hole (the only one in the Milky Way), Sagittarius A, is 27,000 light years away, and now it might be starting to make sense why we’ve never seen one.
What We Can Expect To See Of A Black Hole
The Event Horizon Telescope was pointed around Sagittarius A this year, and now scientists are using the data it has provided to try to get a clear image. What are they expecting to see? As mentioned, because a black hole can’t emit or reflect light, that makes it almost impossible to see. Almost impossible, but not quite impossible. The idea is to make the black hole visible through contrast. That’s why the goal has been to image what’s around the black hole.
A black hole has a border where it is no longer a black hole. This is called an event horizon, where things like gas and dust orbit around the it so quickly, they begin to release gamma and X-rays. The Event Horizon Telescope is looking for those. Once the images from the telescope are translated, scientists are expecting to see something that looks like a shadow on a wall, complete with information about its shape, size, and environment.