UVS (Juno)

[5] Specifically, it is focused on making remote observations of the aurora, detecting the emissions of gases such as hydrogen in the far-ultraviolet.

[6] UVS is one of many instruments on Juno, but it is in particular designed to operate in conjunction with JADE, which observes high-energy particles.

[7] There has been a problem understanding the Jovian aurora, ever since Chandra determined X-rays were coming not from, as it was thought Io's orbit but from the polar regions.

[1] Every 45 minutes an X-ray hot-spot pulsates, corroborated by a similar previous detection in radio emissions by Galileo and Cassini spacecraft.

[16] UVS was developed at the Space Science Department at Southwest Research Institute[17] UVIS data in concert with JEDI observations detected electrical potentials of 400,000 electron volts (400 keV), 20-30 times higher than Earth, driving charged particles into the polar regions of Jupiter.

Juno ' s UVS instrument
Ultraviolet image of Jupiter 's aurora; the bright spot at far left is the end of field line to Io; spots at bottom lead to Ganymede and Europa . This was taken by the Hubble Space Telescope from Earth orbit, using the Space Telescope Imaging Spectrograph
Here is an observation of Jupiter in X-rays by Chandra. CXO's high angular resolution provided a theory-challenging breakthrough—why were the emissions coming from the poles? [ 1 ]
Distribution of acetylene at Jupiter's poles; this data was collected by the CIRS instrument on the Cassini spacecraft during its 2001 flyby of Jupiter. [ 2 ]