Deserts covered in GLASS – sounds like the latest sci-fi film universe!
This is Sandra Tsing Loh with the Loh Down on Science.
In Chile’s Atacama Desert, the sand is littered with football-sized, green-black glass chunks. But these aren’t human artifacts. What sculpted this glass garden?
Geologist Peter Schultz at Brown University and colleagues tackled the mystery.
They collected over three hundred glass pieces from Atacama and put them under an electron microscope. That’s a machine that uses electrons to sketch their chemical structure. Next, they dated soil trapped in the glass using carbon dating. This technique lets scientists pinpoint WHEN the glass was formed – and WHAT it’s made of.
And? It’s SPACE STUFF! Metals in the glass matched NASA samples from COMETS! The date? Around twelve thousand years ago! The twisted structure suggests intense heat and winds. Think ancient AIRBURSTS: fireball comets exploding in our atmosphere! Imagine seeing THAT on your afternoon stroll.
Outer space can transform our planet in bizarre ways. Geologists now have groundwork for researching other potential comet sites.
My guess was giants with beer bottles, but I guess not!
Reference: Schultz, P., Harris, R., Perroud, S., Blanco, N., & Tomlinson, A. Widespread glasses generated by cometary fireballs during the late Pleistocene in the Atacama Desert, Chile. Geology (2021). doi: https://doi.org/10.1130/G49426.1