Jupiter will be the first planet moreover Earth identified to host atmospheric mild exhibits known as “sprites” or “elves.”
Sprites (SN: 6/14/02) and elves (SN: 12/23/95) are two sorts of atmospheric glows that type when lightning alters the electromagnetic surroundings within the ambiance above a storm. On Earth, these electromagnetic upsets trigger nitrogen molecules within the higher ambiance to emit a quick, reddish glow. Sprites can brighten a area of the sky tens of kilometers throughout, whereas elves can span lots of of kilometers (SN: 12/21/96).
Scientists suspected these atmospheric phenomena would possibly seem on different planets that crackle with lightning (SN: 6/19/18). However till now, nobody had seen hints of sprites or elves on one other world.
From 2016 to 2020, the ultraviolet spectrograph on NASA’s Juno spacecraft, in orbit round Jupiter, caught 11 superfast flashes of sunshine throughout the large planet. These flares, reported on-line October 27 within the Journal of Geophysical Analysis: Planets, lasted a median 1.four milliseconds, which is about as fleeting as sprites and elves on Earth. The ultraviolet mild was at wavelengths emitted by molecular hydrogen — the kind of glow anticipated of sprites or elves on Jupiter, whose ambiance is made largely of hydrogen, slightly than nitrogen.
Juno would want to identify a lightning strike on the identical place as one among these brilliant flares to substantiate that they really are sprites or elves, says research coauthor Rohini Giles, a planetary scientist on the Southwest Analysis Institute in San Antonio, Texas. “However there may be moderately good circumstantial proof,” she says. The flashes originated just a few hundred kilometers above Jupiter’s layer of water clouds, the place lightning usually types, and a number of other appeared in identified stormy areas.
Observations of those occasions when Juno is nearer to Jupiter might reveal their dimension, and assist decide whether or not it’s sprites or elves (or each) lighting up Jupiter’s ambiance.