Astronomy Cast Ep. 771: Comet Tails

https://www.youtube.com/watch?v=whMphW1Tb5I


Hosted by: Fraser Cain and Dr. Pamela L. Gay


Streamed live on Nov 8, 2025.


With the arrival of the comet 3I/Atlas (Asteroid
Terrestrial-impact Last Alert System), the world is getting a
crash course in comets, their behavior, and of course their
tails. Today we’re going to talk about comets and their tails,
why they exist, how they grow, why they can be different colors
and how they can be sometimes point AT the Sun.


 


Comets are one of the most animated and ephemeral targets for
astronomy. From night to night they can change in shape and
color, and every nuance tells us something. In this episode, we
decode blue tails, green cores, forward-facing plumes, and other
weird and awesome details observed with these icy visitors. 


 


This show is supported through people like you on
Patreon.com/AstronomyCast


 


In this episode, we'd like to thank: Andrew Poelstra, BogieNet,
Brian Cagle, Burry Gowen, David, David Rossetter, Ed, Gerhard
Schwarzer, Jason Kwong, Jeanette Wink, Michael Purcell, Sergey
Manouilov, Siggi Kemmler, Sérgio Sancevero


 


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