Jupiter spotted giant elves
Scientists at the Southwest Research Institute in the United States have discovered bright ultraviolet flares in Jupiter's atmosphere, similar to sprites and elves on Earth. The phenomenon of transient luminous events (TLE) was recorded using an ultraviolet spectrograph on board the Juno spacecraft. The discovery is reported in an article published in the Journal of Geophysical Research: Planets.
The spectrograph revealed 11 short-term bright flares with a duration of 1.4 milliseconds. They occurred in the atmosphere of a gas giant at an altitude of 260 kilometers above the layer, where the pressure is equal to atmospheric pressure on Earth at sea level (1 bar). The phenomenon cannot be explained by ordinary lightning, which flashes 300 kilometers below. The spectrum of the flares was dominated by ultraviolet radiation of the Lyman series, which arises when electrons pass from excited energy levels in the hydrogen atom to the first. Based on these characteristics, astrophysicists concluded that it was TLE that they observed.
On Earth, TLEs arise in the upper atmosphere in response to outbreaks of tropospheric lightning. Short-term bright flashes include elves, sprites and halos – these are gigantic light phenomena in the form of reddish cones, halos or jellyfish (the color is due to the presence of nitrogen in the atmosphere). Their similar nature with Jupiterian flares is confirmed by the apparent similarity of clouds in the places where the phenomenon occurs. However, on Jupiter, TLEs should be blue or pink due to hydrogen.