AaS! 198: What's So Weird About Black Hole Shadows?
Ask a Spaceman!
Paul M. Sutter
4.8 • 853 Ratings
🗓️ 18 April 2023
⏱️ 32 minutes
🧾️ Download transcript
Summary
How does a black hole make a shadow? What can we learn from it? What are we seeing when we look at a black hole? I discuss these questions and more in today’s Ask a Spaceman!
This episode is sponsored by BetterHelp. Give online therapy a try at betterhelp.com/spaceman and get on your way to being your best self. Visit BetterHelp to get 10% off your first month!
Support the show: http://www.patreon.com/pmsutter
All episodes: http://www.AskASpaceman.com
Follow on Twitter: http://www.twitter.com/PaulMattSutter
Like on Facebook: http://www.facebook.com/PaulMattSutter
Watch on YouTube: http://www.youtube.com/PaulMSutter
Read a book: http://www.pmsutter/book
Keep those questions about space, science, astronomy, astrophysics, physics, and cosmology coming to #AskASpaceman for COMPLETE KNOWLEDGE OF TIME AND SPACE!
Big thanks to my top Patreon supporters this month: Justin G, Chris L, Barbara K, Duncan M, Corey D, Justin Z, Naila, Scott M, Rob H, Justin, Louis M, John W, Alexis, Gilbert M, Joshua, John S, Thomas D, Simon G, Erin J, Jessica K, Valerie H, David B, Frank T, Tim R, Tom Van S, Mark R, Alan B, Craig B, Richard K, Dave L, Stephen M, Maureen R, Stace J, Neil P, COTFM, Stephen S, Ken L, Alberto M, Matt C, Joe R, David P, Ulfert B, Sean M, Edward K, Tracy F, Sarah K, Steven S, Ryan L, Ella F, Richard S, Sam R, Thomas K, James C, Jorg D, R Larche, Syamkumar M, John S, Fred S, Homer V, Mark D, Colin B, Bruce A, Steven M, Brent B, Bill E, Tim Z, Thomas W, Linda C, David W, Aissa F, Marc H, Avery P, Scott M, Thomas H, Farshad A, Matthias S, Kenneth D, Maureen R, Michael W, Scott W, David W, Neuterdude, Cha0sKami, Robert C, Robert B, Gary K, Stephen J, dhr18, Anna V, Matthew G, Paul & Giulia S, Ron D, Steven M, Louis M, Michael C, Alyssa K, Lode D, Roger, Bob C, Patti H, Red B, Benjamin M, BlueDragon, Stephen A, Ian S, James R, Skip M, Robert O, Adam I, Lynn D, Jeffrey C, Allen E, Paul G, Michael S, Jordan, and Colin H!
Thanks to Cathy Rinella for editing.
Hosted by Paul M. Sutter, astrophysicist and the one and only Agent to the Stars (http://www.pmsutter.com).
Transcript
Click on a timestamp to play from that location
| 0:00.0 | Shadows should be rather straightforward affairs, and for the most part they are. I'm walking around |
| 0:14.7 | the beach on a sunny day. I see my own shadow in the sand. How does that shadow get there? Well, |
| 0:20.0 | my body is not transparent, at least |
| 0:22.3 | at visible wavelengths of light, and so the sun's light doesn't pass through my body. The rest |
| 0:27.9 | of the light surrounding me does, and it makes it to the sand, and so there's a pall-shaped |
| 0:32.5 | hole where they can't make it to the sand, because they've been blocked by my body. Shadows. |
| 0:39.3 | Even total solar eclipses, as magical as they are, where the day turns into night and |
| 0:44.2 | everything spooky and there's a ring of fire around the sun, are really just shadows. |
| 0:49.4 | The shadow of the moon is crossing over the planet Earth, and if you happen to line up with |
| 0:53.6 | that shadow, you get a special treat. But it's the same deal. The moon is crossing over the planet Earth, and if you happen to line up with that shadow, |
| 0:54.3 | you get a special treat. But it's the same deal. The moon is not transparent, at least at visible |
| 0:59.4 | wavelengths, and so it carves out a hole of light passing around it. Sometimes astronomers use |
| 1:05.0 | shadows to do some really cool signs. This is how we find exoplanets. An exoplanet crosses in front |
| 1:10.7 | the face of its star, blocks a little bit of the light, casts a tiny, tiny little shadow. |
| 1:15.4 | We see a dip in the brightness. |
| 1:16.5 | We find an exoplanet. |
| 1:18.7 | But it's just shadows. |
| 1:20.0 | Shadows are, well, to be perfectly honest, a little bit boring. |
| 1:23.7 | And that's coming from a guy who tends to find just about any subject fascinating. |
| 1:28.8 | But black holes? Black holes are never boring, and neither are their shadows. In fact, black hole |
| 1:35.0 | shadows are probably one of the strangest things we could possibly take a picture of in the |
| 1:40.6 | entire universe. But first, how do we take a picture of a black hole? It's notoriously |
... |
Please login to see the full transcript.
Disclaimer: The podcast and artwork embedded on this page are from Paul M. Sutter, and are the property of its owner and not affiliated with or endorsed by Tapesearch.
Generated transcripts are the property of Paul M. Sutter and are distributed freely under the Fair Use doctrine. Transcripts generated by Tapesearch are not guaranteed to be accurate.
Copyright © Tapesearch 2025.