New Clues About the Moon’s Origin: Earth and Theia Were Neighbors Before the Crash A new study reveals that Theia — the Mars-sized body that slammed into early Earth and formed the Moon — wasn’t some distant space intruder. It likely formed right next door, in the same inner region of the solar system. 🌍🌑 Scientists analyzed iron isotopes from both Earth rocks and Apollo lunar samples. The match is nearly perfect — meaning Earth and Moon share the same deep chemical fingerprints. That only mak