New observations reveal Jupiters Great Red Spot as mysterious energy source

Researchers from the University of Leicester and Boston University’s (BU) Center for Space Physics report today in Nature that Jupiter’s Great Red Spot may provide the mysterious source of energy required to heat the planet’s upper atmosphere to the unusually high values observed.

The work, led by Dr James O’Donoghue of BU and who is a former Leicester PhD student, was kick-started by a small travel grant from the Royal Astronomical Society back in 2012.

Jupiter is over five times more distant from the Sun, and yet its upper atmosphere has temperatures, on average, comparable to those found at Earth. The sources of the energy responsible for this extra heating have remained elusive to scientists studying processes in the outer solar system. When the BU observers looked at their results, they found high altitude temperatures much larger than anticipated whenever their telescope looked at certain latitudes and longitudes in the planet’s southern hemisphere.

Dr O’Donoghue said: “We could see almost immediately that our maximum temperatures at high altitudes were above the Great Red Spot far below—a weird coincidence or a major clue?”

The extremely high temperatures observed above the storm appear to be the ‘smoking gun’ of this energy transfer, indicating that planet-wide heating is a plausible explanation for the ‘energy crisis.’

Co-author Dr Henrik Melin from our Department of Physics and Astronomy said: “Jupiter is a hot topic with Juno having just entered orbit at the planet.  Leicester is home to the only UK group that is formally involved in this mission, and are directly involved with preparations for the JUICE mission, to be launched in 2022. We are very excited about the new science that these missions will bring.”

Dr Tom Stallard, also from Leicester, added: “Juno will be measuring the aurora and its sources, and we expected the auroral energy to flow from the pole to the equator.  Instead, we find the equator appears to be heated from plumes of energy coming from Jupiter's vast equatorial storms.”