Cheap Astronomy Ep. 121: Black Holes Yet Again!
Cheap Astronomy Ep. 121: Black Holes Yet Again!  
Podcast: The 365 Days of Astronomy
Published On: Wed Jul 23 2025
Description: Very dense and podcastable. Cheap Astronomy finds there can never be too many podcasts about black holes.   Dear Cheap Astronomy – What are squeezars? Squeezars are stars that orbit supermassive black holes. Essentially they are stars on a slow death spiral into the black hole and the squeezing referred to is the tidal stretch being exerted upon them as the orbit closer and closer to the black hole's event horizon. That tidal stretching heats them up, a bit like how the moon of Io, orbiting close to Jupiter is the most volcanically active body in the Solar System. So they are unusually hot and they are also unusually fast.   Dear Cheap Astronomy – Do black holes float in water? Well, the internet says they do so it must be true. But let's unpack this a bit. The internet also says that if you compress the Earth down to marble size it will become a black hole. This is true in a hypothetical sense, but actually compressing the Earth down to marble size is pretty much impossible. You could use some kind of gargantuan press to start the process, but once the Earth becomes denser than the material the press surfaces are made of, the press becomes useless.    We've added a new way to donate to 365 Days of Astronomy to support editing, hosting, and production costs.  Just visit: https://www.patreon.com/365DaysOfAstronomy and donate as much as you can! Share the podcast with your friends and send the Patreon link to them too!  Every bit helps! Thank you! ------------------------------------ Do go visit http://www.redbubble.com/people/CosmoQuestX/shop for cool Astronomy Cast and CosmoQuest t-shirts, coffee mugs and other awesomeness! http://cosmoquest.org/Donate This show is made possible through your donations.  Thank you! (Haven't donated? It's not too late! Just click!) ------------------------------------ The 365 Days of Astronomy Podcast is produced by the Planetary Science Institute. http://www.psi.edu Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org.