The Interstellar Comet 3I/ATLAS: A Time Capsule from the Early Universe
In a captivating episode of StarTalk, renowned astrophysicist Neil deGrasse Tyson and physicist Professor Brian Cox discussed the interstellar comet 3I/ATLAS, which was detected by the Asteroid Terrestrial-impact Last Alert System (ATLAS) on July 1, 2025. This comet, estimated to be 7-8 billion years old, has traveled for 10 billion years from a distant star system older than our Solar System. It presents an extraordinary opportunity to study material from a distant star system, but it has sparked misinformation and silly claims that it could be an alien spacecraft.
"It's a fascinating thing that current estimates say is maybe 7, 8 billion years old, has come from a distant star system older than our Solar System," Cox explained. "An unprecedented opportunity to observe material that's coming from a distant star system. And yet you see people going 'it's aliens.'"
Tyson and Cox, along with regular Star Talk guest and comedian Chuck Nice, humorously addressed the idea that the comet is an alien spacecraft. They pointed out the absurdity of aliens creating spacecraft that mimic comets, especially considering the comet's close miss of Earth. The comet will make its closest approach on December 19, 2025, at a distance of 270 million kilometers, which is far from Earth's closest approach to any planet.
"By the way, if it's an alien spaceship, it's not spending much time [here]," Cox added. "It misses the Earth by what is it? Two astronomical units."
The comet's hyperbolic trajectory and its departure from our Solar System after a brief visit offer a unique glimpse into the ancient universe. As Cox and Tyson noted, this interstellar visitor provides an exciting opportunity to study the early universe without resorting to alien conspiracy theories. The comet's journey through space, spanning billions of years, highlights the vastness of the universe and the potential for discovering more ancient objects in the future.
