Artist rendering of interstellar object ‘Oumuamua
Artist rendering of interstellar object ‘Oumuamua

Dark Comets with Darryl Seligman

Arndt Stelter, CC BY-SA 4.0, via Wikimedia Commons
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About This Episode

Why did Oumuamua, the first discovered interstellar object, accelerate faster than it should? Neil deGrasse Tyson and comic co-host Chuck Nice dive into the mysteries of the newest objects in the solar system: “dark comets” and interstellar objects with astrophysicist Darryl Seligman. 

We kick things off by revisiting one of the most fascinating astronomical events of recent times: the discovery of Oumuamua in 2017. This interstellar object, detected by the Pan-STARRS telescope, left scientists baffled with its hyperbolic orbit, indicating it came from beyond our solar system and would never return. Learn how its unexplained acceleration expands our conventional understanding of celestial objects.

Darryl sheds light on the mysterious forces at play, from hydrogen ice sublimation to radiation pressure, that could be propelling Oumuamua. Discover how these anomalies might suggest a new category of “dark comets” that harbor icy material but evade detection due to their low albedo and lack of dust tails. We discuss how this could change how we detect and study such objects, potentially uncovering more interstellar visitors.

Plus, what role might dark comets play in our understanding of the origins of water on Earth? As we look ahead, the upcoming Vera Rubin Observatory promises to revolutionize our understanding of these enigmatic travelers by scanning the southern hemisphere’s sky with unprecedented precision. Learn about the Japanese Hayabusa II Mission to go to a dark comet. Darryl predicts a surge in interstellar discoveries that could expand our knowledge of these elusive objects and even hint at their role in delivering water to Earth. How might the discovery of more interstellar objects with the Vera Rubin Observatory impact our understanding of the solar system and the galaxy?

Thanks to our Patrons デーモン, Howard Chang, Kelly Houle, John Herron, Justin Hanson, Melshore Walker, Andrei L, JENNY JONES, Rebecca Fishow, Alin Simionoiu, Steve C, Johnathan Gregory, Jake Evans, Jim Shorts, Jessica Hudzik, William Komanetsky, and Thierry Querette for supporting us this week.

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In This Episode

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