science ๐ฌ Tiny Earth Crystal Dates to Moon's Final Chill
A fingertip-sized zircon crystal from Western Australia's Jack Hills was dated to 4.404 billion years ago. This ancient fragment was first identified by Simon Wilde and colleagues in 2001, with subsequent confirmation in 2014. This age closely matches a 2025 study pinning the Moon's final crystallization around 4.429 billion years ago. This suggests Earth and the Moon were cooling down at nearly the same time after the massive impact. The findings push back the timeline for early surface water and potentially life on Earth. ๐