NASA's Cassini spacecraft and the Hubble Space Telescope teamed up to observe Saturn’s poles in 2013. Other the course of two months, Hubble captured images of aurora in Saturn’s north pole in ultraviolet light while Cassini provided images in ultraviolet and infrared.
According to NASA, Hubble was trained on Saturn’s north pole while Cassini’s position around Saturn let the spacecraft observe the north pole as well as the south pole, which cannot be seen from Earth. The auroras were the result of a solar outburst in March 2013. Solar wind, charged particles, reacts with a planet’s atmosphere creating a spectacular show that can be seen at the poles. The auroras occurred in April and May.
The auroras on Saturn are similar to those seen on Earth with the main difference being in color. On Earth auroras are green and red while Saturn’s auroras are purple and red. The reason for the color difference is the composition of the charged particles in the atmosphere, Earth contains nitrogen and oxygen molecules while Saturn’s atmosphere contains hydrogen molecules, notes NASA.
Jonathan Nichols, from the University of Leicester in England, led the team working on the Hubble images and aid in a statement, “In 2013, we were treated to a veritable smorgasbord of dancing auroras, from steadily shining rings to super-fast bursts of light shooting across the pole."
The images reveal several features of auroras on Saturn including emissions that disappear and reappear in different photos as well as bright features that are seen in several photos that rotate slower than Saturn's rotation rate.
New connections being created between magnetic field lines may explain the bright aurora storms, notes NASA. The images also indicate Saturn's moons may affect auroras as one birght area was rotating with Mimas' orbital position.
The observations can also lead to new insights on the atmospheres of gas giants, including rhow charged particles travel around the planet, notes NASA.
The video combining Hubble and Cassini images can be viewed below.