We all know what comes out of the bottom of thunderclouds: lightning. But what comes out of the top? Red sprites. High above Earth on May 10th, astronauts onboard the International Space Station watched a cluster of the red forms explode from the top of a powerful thunderstorm located between Los Angeles and Las Vegas:



Spaceweather.com reader Frankie Lucena of Cabo Rojo, Puerto Rico, noticed the sprites in a time lapse video of lightning NASA released last week. "The space station was over California and traveling northeast when they took the picture," notes Lucena.

The photo shows how high sprites can go, reaching all the way from the thunderstorm to a layer of green airglow 100 km above Earth's surface. This means sprites touch the edge of space, alongside auroras, meteors and noctilucent clouds. They are a true space weather phenomenon. 

Solar Minimum may be boosting sprites. During this phase of the solar cycle, cosmic rays from deep space penetrate Earth's atmosphere more than usual--a result of the sun's weakening magnetic field. Some researchers believe that cosmic rays may provide the ionizing "spark" that triggers many sprites. If so, stay tuned for more as Solar Minimum deepens.
Bron: spaceweather.com