If the M87 black hole picture (more accurately, an image of its shadow) taken by the Event Horizon Telescope (EHT) didn’t blow your mind when it made the internet explode last week, that picture could soon be eclipsed by a video.
The EHT will soon produce the first movie ever of blazing gas swirling around a black hole. This won’t just be an animation figured out by an algorithm plugged into a computer. A video is possible because this black hole is so gargantuan that the gases in its accretion disc take forever to get around it even once. So as project leaders recently said at this month’s meeting of the American Physical Society, you’ll soon be seeing an actual video of an actual black hole eating actual star stuff.
Because the EHT is made up of radio telescopes across the planet that merge precisely timed recordings of radio waves all at once, it has the power to image a black hole. More telescopes are being incorporated into this behemoth to give it even greater capacity to make what we once thought were impossible recordings. Meaning, we will be seeing black hole images in more detail — HD compared to the one we just glimpsed — and movies of black holes devouring stuff around them like the cosmic monsters they are.
"It turns out that even now, with what we have, we may be able, with certain prior assumptions, to look at rotational signatures [evidence of the accretion disk swirling around the event horizon]," said EHT team lead Shep Doeleman, a Harvard University astronomer. "And then, if we had many more stations, then we could really start to see in real time movies of the black hole accretion and rotation."
Those stations are what will be combined into a movie that will make it seem as if you’re watching the black hole, now named Powehi or “embellished dark source of unending creation” in Hawaiian, gobble up matter much faster than it actually does. Powehi is 6.5 million times the mass of our sun, with its event horizon the size of the solar system. Just to give you an idea of how vast our solar system is, Voyager 2 traversed it for over 40 years and just broke through to insterstellar space.
The immensity of it all is why the EHT is going to have a really easy time shooting a video. There is no significant change in what Powehi’s accretion disc looks like for about a day here on Earth, so the telescopes will only have to image it every 24 hours or so to get a new frame. There is also plenty of time left if the team wants to make any additional movies or a time-lapse version.
Whatever this movie comes out looking like, it’s going to be a blockbuster.