It's an asteroid named 2024 PT5, which entered Earth's orbit on Sept. 29 and will be caught there until Nov. 25, before flying away back into the solar system. Scientists call such phenomena mini-moons.

If you were hoping to see the “mini moon,” you’ve probably been disappointed. But experts say the asteroid was an important milestone in planetary defense research.

A small asteroid called 2024 PT5 will temporarily orbit Earth this fall. Here's what it looks like and whether it will be visible to the naked eye.