How Do You Observe a Black Hole?

Black holes may hold the key to understanding the most fundamental truths of the universe, but how do you see something that’s, well, black? Astronomers think they have the answer. Thanks to a global array of radio telescopes that turn the Earth into a giant receiver, we’ve imaged one black hole (Messier 87) and may soon have the first picture of the event horizon of Sagittarius A*, the black hole at the center of the Milky Way galaxy.

PARTICIPANTS: Shep Doeleman, Andrea Ghez

MODERATOR: Brian Greene


This program is part of the BIG IDEAS SERIES, made possible with support from the JOHN TEMPLETON FOUNDATION.

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0:04 – Understanding escape velocity and black holes
9:25 – Panelist introductions
10:41 – Are black holes really out there?
12:06 – What resides in the center of our galaxy?
13:45 – Evidence of black holes
20:26 – Kek telescope experiment
24:43 – Event Horizon Telescope
32:21 – Simulating a black hole
34:27 – Will we find a deviation from Einstein’s theory?
36:24 – What’s the next phase of our understanding of gravity?


– Produced by John Plummer
– Associate Produced by Laura Dattaro
– Animation/Editing by Josh Zimmerman
– Music provided by APM
– Additional images and footage provided by: Getty Images, Shutterstock, Videoblocks

This program was recorded live at the 2018 World Science Festival and has been edited and condensed for YouTube.

Watch the full unedited program here:
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