Let’s take a look back at our own planet for a moment with this stunning photo captured from the Space Station. This shot, taken on the night of Aug. 10, 2015, shows lightning flashes in thunderstorms over southern Mexico. Along the right edge bright red and purple streamers can be seen extending high into the atmosphere above a particularly powerful flash: a full-on “red sprite” caught on camera!
So-called because of their elusive nature, sprites typically appear as several clusters of red tendrils reaching upwards from the region of a lighting flash, extending as high as 55 miles (90 km) into the atmosphere. The brightest region of a sprite is usually around altitudes of 40-45 miles (65-75 km). They don’t last very long, 3-10 milliseconds at most, and so to catch one on camera is a real feat (or a great surprise!). Sprites have been photographed from the ISS before (it’s a great place from which to observe these phenomena, which are often obscured by the storm clouds they occur above) but this is one of the best images I’ve seen yet.
And in case you’re wondering, that’s the Moon (not the Sun) lighting the star-filled sky, and the yellow-green light surrounding the planet isn’t the aurora – it’s airglow. A corner of an ISS solar array can be seen at the upper right too. Read more about red sprites in an article I wrote for Discovery news here, and if you are really interested in them be sure to check out the PBS NOVA special “At the Edge of Space,” which highlights some of the best research done on sprites.