How Do You Take a Picture of a Black Hole?

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The Joy of Why

How Do You Take a Picture of a Black Hole?

By

Janna Levin

and

Steven Strogatz

October 29, 2026

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Black holes are one of the universe’s most exotic and elusive objects. When nothing, not even light, can escape their powerful gravitational grasp, taking a picture of one seems unimaginable. But an image of a black hole, or more accurately its shadow, could offer insights that theory alone may not provide when testing predictions. So how can it be done?

Harvard astrophysicist Shep Doeleman and a team of 250 researchers achieved this extraordinary feat by linking a group of radio telescopes around the world. This network, called the Event Horizon Telescope, produced the first image of a supermassive black hole in the galaxy M87, around 55 million light-years away, and the first image of the black hole at the heart of our galaxy. In this episode, Doeleman tells co-host Janna Levin how he turned the Earth into a telescope capable of seeing a black hole, the incredible level of science and collaboration that was required to achieve this, how the images have furthered our understanding of these exotic objects, and how movies of black holes may be possible by the early 2030s.

Listen on Apple Podcasts, Spotify, TuneIn or your favorite podcasting app, or you can stream it from Quanta.

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Transcript

 JANNA LEVIN: Okay. I’m Janna Levin

STROGATZ: A podcast from Quanta Magazine where we look at some of the biggest unanswered questions in math and science today.

LEVIN: Great to see you. I’m pretty excited about this one. I cannot deny or hide it. We’re talking about not only an area where I’ve spent a lot of my life black holes — the greatest, strangest topic out there — but also I had a chance to talk to an old friend. So it’s a fun episode, I hope.

STROGATZ: I’m really looking forward to hearing it. I know you’ve always had a special affection for black holes. I’ve had a chance to interview you in some earlier version of this.

STROGATZ: And you blew my mind over and over about black holes.

LEVIN: Yeah, they require some defense. They’ve got a bad reputation, not entirely earned.

STROGATZ: What’s the bad reputation? Because they like to eat things?

LEVIN: Yeah. You know, black holes, kind of this monster truck language around black holes all the time. You know, they’re like… But actually, black holes are remarkably elegant, clean, simple systems. They leave you alone if you leave them alone. They’re actually quite small for their heft. That’s kind of their whole gestalt, that they’re actually tiny for their heft.

And, uh, you know, though they’re the darkest phenomenon in the universe, they figure out a way to become the brightest beacons that we see on the edge of what’s observable.

LEVIN: So, they’re, they’re pretty awesome. I also think that they’re fundamental to physics, unlike any other macroscopic object you can think of.

STROGATZ: Hmmm. When I think of black holes, I tend to focus on what they do to spacetime. You know, that they cause singularities. It’s their geometry that always grabs me. But that’s not really necessarily the only way to think about black holes. They’re really objects. Real players.

LEVIN: Yeah. I think after people got over the thrill that they actually existed out there and that they could indirectly be detected, there was a sense that they’re not major players in the universe. “Eh, so there’s some black holes out there.”

Quite to the contrary, I think we’ve come to understand that they sculpt our history and our past, that they have a very regulating and important role in determining the shape and size of galaxies and where there might be habitable regions even. And ultimately, we’re kinda doomed to fall into black holes eventually. So, they’re kind of our past and our future.

But, it might surprise people that we had never actually taken a picture of a black hole. All of our evidence had been indirect until about 10 years ago, and that group worked for well over a decade, for some people up to two decades, to try to capture the first picture of a black hole.

LEVIN: It was a tremendous accomplishment, led by Shep Doeleman, who is our guest. So let me tell you about Shep. Shep is a senior research fellow at Harvard University, the assistant director of Harvard’s Black Hole Initiative, also an astrophysicist at the Smithsonian Astrophysical Observatory.

And he was the founding director of the Event Horizon Telescope Consortium, which is a network of observatories around the world which gave us the first and only images humanity has ever captured of black holes.

STROGATZ: Hmm. This sounds like it’s gonna be a great discussion of science at its best.

LEVIN: Yeah, it’s an epic story. Let’s hear from Shep himself.

SHEP DOELEMAN: It’s good to be here, Janna.

LEVIN: It’s a pleasure to have you on the show. I’m really curious if you remember not just your way into black holes, but your way into the entire idea of thinking about the universe?

DOELEMAN: Wow. Well, everybody falls in love with astronomy at some point. I don’t care who you are, you fall in love with astronomy. And whether it’s staring up at the night sky, you know, at summer camp or seeing a meteorite, for me, it was seeing a total solar eclipse. I was 13, 1980. And my parents took me out to the middle of the desert in Oregon and at first we thought we weren’t gonna see totality, the clouds were moving in, and then the clouds just parted and we saw this amazing eclipse. It was just tremendous.

LEVIN: Did you think at that moment, “Well, this is what I’m gonna do for the rest of my life”? Or is it that the memory comes back and we reconstruct the story, you know?

DOELEMAN: That’s a great question. I think it mostly, it just comes back. Life isn’t linear like that. But I will say the idea that there would be these huge objects that were moving and they could align perfectly and allow you to see what would normally be hidden, like the corona of the sun, was startling to me. I mean, it didn’t have to be that way. Like, the angular diameter of the moon doesn’t have to be the same as the sun so they totally block each other out. But these coincidences sometimes give you a special view into nature.

LEVIN: Yeah. I, I love that there’s just this idea that we’re inspired by the firmament, science’s oldest instrument, and that we all have it in common.

Um, so I really feel we have to make a confession ’cause we’ve known each other a really long time. I feel like we met maybe the first week of graduate school at MIT. I think over a cookie table.

LEVIN: So I remember just you were always trying these crazy ideas in graduate school. You were like a creative curiosity in search of a problem. Tell me a little bit first about how you landed on this idea of pursuing a portrait of a black hole?

The idea that there would be these huge objects that were moving and they could align perfectly and allow you to see what would normally be hidden, like the corona of the sun, was startling to me.

LEVIN: Oh, you didn’t have to say the year, man. That was unnecessary [laughs].

DOELEMAN: I know, when the Earth was cooling. But, I cast around a bit. I started in the X-ray group there, and then I did a little bit of neuroscience looking at biophysics. And then I was introduced to this idea of turning the Earth into a telescope, and this experiment that we use to image black holes and that immediately drew me in.

LEVIN: Yeah. So we’re gonna talk about this project, but when you were in graduate school, what was the status of black holes scientifically? Were they detected? Did everyone believe that they were real astrophysical phenomena?

DOELEMAN: There was really a sense that black holes existed or strong evidence for them. And of course, there are two flavors of black holes. There are stellar-mass black holes which form during star death. So when a star goes supernova, it will explode the outer shells off, and then the interior part will collapse and if the star is massive enough, it will turn into a black hole, and that black hole could be tens of solar masses.

But then there are these behemoths, these supermassive black holes that live in the centers of galaxies. And while there can be many stellar-mass black holes in a galaxy, there’s probably just one, maybe two, supermassive black holes at the core of any given galaxy.

And for the stellar-mass black holes, people had seen these X-ray binaries, and they were seeing very fast fluctuations in X-rays and even in the radio from these stellar-sized sources. And everything fit with this idea that there was a black hole eating another star that goes an X-ray binary.

LEVIN: And that was Cygnus X-1, a first X-ray object in the direction of the constellation Cygnus, right?

DOELEMAN: Exactly, it was those kinds of sources. And then the radio people predominantly had seen some very high-resolution images that were very troubling. So you would see in the optical, a galaxy would look like a normal run-of-the-mill galaxy with a lot of optical light coming from stars.

But then if you looked at it in the radio, you would see these oppositely directed jets of material all tracing to the center of the galaxy. What is causing that?

And the best idea that people had for that was a spinning supermassive black hole that was energizing jets that moved at near light speed from the north and south pole of that black hole, and it was piercing the entire galaxy.

So from two completely different lines of inquiry you had one flavor of black holes being suspected from the X-ray, and you had another suspected predominantly by the radio.

LEVIN: So even though people started to theorize that these must be black holes, nobody had taken a picture of a black hole, not in the ’70s, ’80s, ’90s, the noughts. I think that was a surprise to people because we talked about them as being such compelling inhabitants of the universe, death states of stars, but we had actually technically never seen one directly. Never taken a portrait. And that’s really what you set out to do in many ways.

DOELEMAN: Yeah. I think the simplest way of saying it is that seeing is believing in a certain way. I mean, you can theorize something, but actually seeing it confers a reality on things that you don’t get otherwise. And there were some really important signatures, too. It wasn’t just seeing it. It was measuring it. Taking the measure of the thing not only gives you confidence in its reality, but you can test predictions.

So in 1915, when Einstein came with his theory of general relativity, which governs the space time around a black hole, and then the year after that Schwarzschild solved it in the trenches of World War I, a story that we know well, even after that, it was pretty clear that if you went to the conclusion of tha