It’s been 6 years since the Event Horizon Telescope (EHT) released the first photo of a black hole, and 3 years since we unveiled the one in our own galaxy. For Black Hole Week 2025, we’ll be answering your questions this Friday from 3:00-5:00 pm ET (19:00-21:00 UTC)!
The EHT is a collaboration of a dozen ground-based radio telescopes that operate together to form an Earth-sized observatory. As we continue to delve into data from past observations and pave the way for the next generation of black hole science, we’d love to hear your questions! You might ask us about:
- The physics and theories of black holes
- How to image a black hole
- Technology and engineering in astronomy
- Our results so far
- The questions we hope to answer next
- How to get involved with astronomy and astrophysics
- The next generation Event Horizon Telescope (ngEHT), which will take black hole movies
Our panel consists of:
- Shep Doeleman (u/sdoeleman), Founding Director of the EHT, Principal Investigator of the ngEHT
- Dom Pesce (u/maserstorm), EHT Astronomer, Project Scientist of the ngEHT
- Prashant Kocherlakota (u/gravitomagnet1sm), Gravitational Physics Working Group Coordinator for the EHT
- Angelo Ricarte (u/Prunus-Serotina), Theory Working Group Coordinator for the EHT
- Joey Neilsen (u/joeyneilsen), EHT X-ray Astronomer, Physics Professor at Villanova University
- Felix Pötzl, (u/astrolix91), EHT Astronomer, Postdoctoral Researcher at the Institute of Astrophysics FORTH, Greece
- Peter Galison (u/Worth_Design9390), Astrophysicist with the EHT, Science Teams Lead on the Black Hole Explorer mission, Director of the Black Hole Initiative at Harvard University
If you’d like to learn more about us, you can also check out our websites (eventhorizontelescope.org; ngeht.org) or follow us u/ehtelescope on Instagram, Facebook, X, and Bluesky.
Comments
How does a picture of a black hole advance our knowledge precisely? Does it improve our understanding of gravity or black holes? Does it constrain possible modifications of gravity?
Remember the announcements and was rapt by the announcements and images. Sadly I don’t have the math or physics background to ask any intelligent questions but am a supporter anyway. Thanks and have a great weekend!
What do you need to make a higher resolution picture?
What are the answers that you’ve found with the pictures to questions that were completely contrart to your assumptions?
Also, how mich yomama jokes have you made about black holes as a team?
Whats the coolest this you guys have learned about this black hole? And is it unique to other black holes?
Are there any galaxies whose distance and mass make them candidates for similar projects? If so, can you speak to if any are in the works?
What is your favorite thing you’ve learned during the project?
How long does your team estimate it’ll take for the ngEHT to be developed and capable of taking video?
I remember this picture taking the Internet by storm, excited to see more!
Thank you very much for your work!
My question is: how many GBs of data did you have to process to get the picture of Sagittarius A?
What is the next major project for your team? I would love to know what endeavours you’re taking on next.
Can you describe what you think this would look like in 3D? Was Interstellar close (and are you fans?!)
If Planet Nine is actually a primordial black hole, is there any measurement we can take to prove it? And if it was confirmed, what would be the next measurement or experiment you’d be most excited to see?
Looking up to the stars, I wonder if you also longing to be there too, wonder how constellation looks like on other planet?
Are there any other ways to interpret this image (before it was edited) than a black hole?
Hello, a layman here.
Would you please explain how these images are captured and analyzed? And, since there should be more data now than before, could the image be improved further?
Why was the black hole in M87 chosen as the first target for imaging, instead of the one at the center of our own galaxy (Sgr A)?
What would it sound like to be standing on/in a black hole if we were capable of surviving the intense forces?
Would it be practical to extend the baseline by sending radio telescopes to the outer solar system?
What are you working on now?
And do you use AI for any part of your work?
How certain are we that the interpreted data has this actual shape, and how repeatable is the process? Will any other team get the exact same image if they use the raw data completely independently?
Is there any benefit to observing an area that is a known Gravitational lens area? Or are the distortions and repetions of objects appearing to be “lensed” make such EHT observations not worthwhile?
Are black holes the end of matter or beginning of matter?
I’ve wondered why this photo of the black hole does not look like the ones we see in movies. Is it true that the image is a top down view of the black hole with its accretion disk? How do you know it’s a top down view? Wouldn’t gravity still loop the light from the accretion disk around to make it have that curve at the top, curve at the bottom, and a line splitting the middle across the black hole? Why does our image not have the line in the middle?
Awesome work guys! What would you say are some of the most intriguing still-unanswered questions about black holes or in astronomy/astrophysics in general?
Is there suspected to be “quark matter” inside black holes like there is suspected to be inside large neutron stars?
Oh this is awesome, thanks for doing this AMA! It’s incredible what your team has achieved, never thought I would see something like this in my lifetime.
What are the current efforts to improve our capabilities in producing images like this? Is it likely in the semi-near future to have radio telescopes in orbit around other celestial bodies to add to the EHT array?
How far is current research in supporting the idea of Wormholes? Or is it entirely disregarded?
Even if we manage to find one, do you think (theoretically) it would be possible to travel one or are the odds too far against us?
How does the density of interstellar dust, as sparse as it may be, affect your ability to image distant objects?
Have you guys been able to determine the precession of Sag A and M87 ? In other words , and in particular for sag A , we now know that it’s jets are pointed almost directly at Earth , but the solar system orbits around the galactic center every 230 million years . Knowing Sag A‘s precession would allow us to know when exactly the solar system might have been aligned with the black holes’ polar jets and see if it coincides with events on Earth or if they could have played a role in the early solar system .
In this 2D image, it appears that the black hole is a sphere with a ring of light around it. Why would the light be in a “ring shape” and not spherically covering the black hole?
I also have this question for why galaxies, solar systems, etc also develop in 2D disk shapes rather than 3D shapes
What is your favourite “fun fact” about Sagittarius A*? Also, could you share any links of your publicly available papers?
If we put a telescope on the Moon and it worked in concert with the EHT telescopes, how much could we improve the resolution of Pōwehi?
do you plan on releasing a full detailed rebuttal to the team of Miyoshi, Kito & Makino’s claims that the M87 and Sag A images have been interpreted incorrectly or in a biased way? it’s been of an increasingly popular opinion among online astronomers that the hole is merely an artifact, and though your team has held strong in your observations, you haven’t given much detail to rebuke Miyoshi et al aside from a brief dismissal on your website.
are you currently working on, or planning on, a detailed response to Miyoshi and his team or is this something you have no intentions of entertaining?
Do you believe that the light and/or matter that surrounds the black hole around the event horizon, would actually be there if you were to somehow able to view it from within the event horizon? Or could it be that the light is trapped there from our perspective due to the extreme time dilation being that close to it, the actual ‘matter’ having long already fallen in?
From what I’ve heard, black holes might contain a singularity. If you entered a black hole you would fall towards it in time, but not distance, never getting closer to it.
What would happen to the singularities if two black holes merges. Would the new black hole have two singularities or just one?
The closer you get to a black hole, the more you slow down for an outside observer until you got the event horizon and stop.
When two black holes merges, will it then look like two spheres touching (observed by the disks around them), or would it become a single sphere?
What’s the next black hole that’s going to be imaged by the EHT?
Scientists! What new information have you learned about black holes from imaging one?
Cubert~ “That’s it, Brett. You’ve compressed our lunches to a singularity for the last time! Salt him, Dwight”!
Thank you for your dedication and hard work!
How much of the original core team is still working on the project?
what other kinds of astronomical structures can you image in high fidelity using the same radio interferometry technique? galaxies? nebula? solar systems?
What are the next steps in improving angular resolution and fidelity? better/more sensors? Space based sensors? AI/compute?
can you combine your results with other wavelengths such as IR, visible, etc… for full spectrum measurements?
I remember from the reveal press conference that it was mentioned that the amount of data collected was absurd, needing to be transported by plane (which would have more “bandwith” than over the net). This data was then analyzed independently to assure that the final result was coherent/true. Is this the standard operation or was for this specific case. Also, is this in any way interfering in how much data you can collect and thus what you can observe/target? Finally, can you share what are your future goals with this project in terms of what you use this “telecope” for?
Thank you very much! It is an awesome endeavor to take to answer some very awesome questions!
I remember from the reveal press conference that it was mentioned that the amount of data collected was absurd, needing to be transported by plane (which would have more “bandwith” than over the net). This data was then analyzed independently to assure that the final result was coherent/true. Is this the standard operation or was for this specific case. Also, is this in any way interfering in how much data you can collect and thus what you can observe/target? Finally, can you share what are your future goals with this project in terms of what you use this “telecope” for?
Thank you very much! It is an awesome endeavor to take to answer some very awesome questions!
Thanks for this AMA! What can we, your audiece, do regularly to help grow public interest and investment in astrophysics? Also, while astrophysics and black holes are certainly interesting AF, is there anything we can do to support turning that into applied science that benefits society even more directly?
What part of the math used to generate these images was the most computationally intensive?
Is it a limit on how many images you can produce, or is there some other bottleneck?
Can the same recorded data be used to generate images of multiple objects, or do you have to record separately for each one?
You have been imaging each year since 2017 (except maybe 2020?), but we have only seen images from 2017 and 2018 data. When will we see images from the latest observation runs? I’m so excited to see how the black holes change over the years.
I still have a print out of this on the cover of the newspaper when it came out, it was so amazing! What are you looking forward to most regarding the future direction of this project?
Any chance of getting a third hole imaged?
In the picture, which direction is it rotating? Where is the equator and axis?
How do you feel about the theory that our universe could be in a black hole?
with the estimated 100 million black holes in the milky way galaxy and vera rubin observatory coming online soon if we find a blackhole close enough will you try to image it?
Is there something you feel was underreported, and not many people are aware of?
For the computations involved the theory with the interferometry, that theory should be able to be applied to getting higher resolutions on smaller scales, no? e.g. if there were pictures of an eclipse from lots of cameras or if there were a lot of videos (audio data) of an earthquake or volcanic eruption?
When taking the picture, did you ever have to wait because a star was obscuring it?
Couldn’t the massive curvature of space-time caused by the central black holes in galaxy centers also play a role in the topic of dark matter, i.e. that galaxies do not fly out of the galaxies despite insufficiently visible matter?
Do you have a personal favorite artist’s impression of one of these black holes that you think is THE most accurate? For example, all black hole fanboys know that while Interstellar is great, it does not show the dimming or the color change between the left and right side. Could you post some of your absolute favorite images/videos here? And could you post at least one that would be accurate as seen with actual human eyes (ok maybe not as bright but everything else accurate)?
Just finishing up an astronomy course. Last thing we learned was that in the beginning of the universe, the energy was so dense that matter was not able to form. Is a black hole similar in this aspect? Past the neutron degeneracy pressure is the matter converted back into energy?
My 8 year would love to know how do black holes shrink?
No question, just a plug for the National Science Foundation which funded your work and is in the process of being diorama dismantled.
How many scientists work on this project, and who do they consist of? Are the majority professionals with degrees? Did you have undergraduate/graduate interns help?
How does the EHT handle clock sync across the member telescopes? (Paper reference too as this has got to be a longer answer than fits into Reddit format)
As understand, If I fall in to a black hole, and I look out, the time if the universe will increase, and eons of time will pass on the outside. And hawking radiation will slowly evaporate the hole, does that mean that I’ll never reach the center, but the hole will completely evaporate before I reach the center? Can anything reach the center of the hole?