Red sprites and green gravity waves are rare space weather phenomena.
They were caught both over New Underwood, South Dakota in a single shot! Amazing!
As northern summer comes to a close, electrical storms are rumbling across the USA. After nightfall, red sprites can be seen dancing across the cloudtops. On Aug. 20th, Tom A. Warner photographed these specimens above :
He saw not only sprites, but also green-glowing gravity waves. The waves are, literally, the ripple effect of a powerful thunderstorm on the mesosphere some 80 km above Earth’s surface.
From space, these waves look like a giant atmospheric bull’s eye. From the ground, they appear to be green ripples in the sky. Left to themselves, gravity waves would be invisible to the human eye. We see them, however, because they are colored green by an aurora-like phenomenon called “airglow.”
Airglow is caused by an assortment of chemical reactions in the upper atmosphere driven mainly by solar ultraviolet radiation. Gravity waves rippling away from the central axis of a thunderstorm cause temperature and density perturbations in the upper atmosphere.
Speaking simplistically, those perturbations alter the chemical reaction rates of airglow, leading to more-bright or less-bright bands depending on whether the rates are boosted or diminished, respectively.
Here the video timelapse of the same night:
Red sprites, green gravity waves and airglow. What space weather phenomena do you want more on a picture? Yes a meteor is missing!
