#GreenGhosts were discovered in May 2#019 by Hank Schyma, a Houston Texas-based storm chaser. Initially, researchers thought they might be a form of green airglow activated by sprites when they touched a layer of oxygen 80 to 90 km above Earth's surface. Indeed, Ghost is an acronym: "Green emissions from excited Oxygen in Sprite Tops."

New research casts doubt on that explanation. A paper recently published in Nature Communications reports a Herculean effort to decode the color of Green Ghosts. About a month after Schyma discovered the phenomenon, a team of lightning scientists led by María Passas Varo of the Instituto de Astrofísica de Andalucía began chasing thunderstorms, hoping to catch a Green Ghost in the slit of their spectrograph. It wasn't easy. Green Ghosts appear unpredictably and often last for no more than a fraction of a second. Four years and 2000 spectra later, they managed to capture just one spectrum of a Green Ghost strong enough to study. The results surprised them.

#Green #Ghosts, it seems, are made of #metal.

https://spaceweather.com/