A giant asteroid hit Earth, but its crater is missing

Researchers discovered a new field of ancient tektites in South Australia, revealing a long-forgotten asteroid impact. These 11-million-year-old glass fragments differ chemically and geographically from other known tektites. Although the crater remains missing, the find exposes a massive event once thought unrecorded, offering clues to Earth’s tumultuous past and planetary defense.

from Top Health News -- ScienceDaily https://ift.tt/2GYCw3j