Interstellar visitor 3I/ATLAS swings by Earth soon
Heads up, space fans: the interstellar object 3I/ATLAS is making its closest pass by Earth on December 19, 2025—though it'll still be a safe 170 million miles away.
Scientists are excited because this rare visitor gives them a unique look at something from outside our Solar System.
What's really caught their attention? A repeating "heartbeat" of light pulsing every 16.16 hours.
What's behind the mysterious heartbeat?
Harvard astronomer Avi Loeb suggests this pulse might come from the object spinning, kind of like a cosmic lighthouse.
Even though it's from deep space, 3I/ATLAS acts a lot like some comets we know, with solar radiation possibly creating an unusual anti-tail.
Most experts think these are natural effects, but Loeb says we shouldn't rule out more surprising possibilities just yet.
With its close approach coming up, astronomers are eager to gather more clues and see what secrets this traveler might reveal.