Tantalizing Remains of an Ancient Earth-Shaking Asteroid

Tiny glass beads scientists have discovered on what used to be ocean floor tell the tale of a giant asteroid that hit the earth billions of years ago. The beads are called spherules and scientists from the Australian National University found them in far Northwestern Australia. The asteroid 20 to 30 kilometers across would have left a crater hundreds of kilometers wide when it hit. That's a big asteroid A rock that size would also, have triggered "earthquakes orders of...

© La Voix de l'Amérique - lundi 16 mai 2016