The northern and southern lights of Jupiter pulse independently - unlike the Earth’s auroras - according to new research which includes expertise from the University of Southampton.

The study, published in Nature Astronomy, used the European Space Agency’s XMM-Newton and NASA’s Chandra X-ray observatories to make discoveries that could support the understanding of other bodies across the Universe such as brown dwarfs, exoplanets and even neutron stars.

Dr Caitriona Jackman, an Associate Professor of Space Physics at Southampton’s Department of Physics and Astronomy, contributed to the study which was led by Dr William Dunn from University College London (UCL).

The study found that very high-energy X-ray emissions at Jupiter’s south pole consistently pulse every 11 minutes. Meanwhile those at the north pole are erratic: increasing and decreasing in brightness, independent of the south pole.

This behaviour is distinct from Earth’s north and south auroras which broadly mirror each other in activity. Other similarly large planets, such as Saturn, do not produce any detectable X-ray aurora, which makes the findings at Jupiter particularly puzzling.

“Jupiter’s auroral X-ray emissions are the most powerful in our solar system, and their study provides unique insight into the origin, dynamics and acceleration of charged particles in the Jovian magnetosphere,â€? Caitriona explains. “Now is a fantastic time to study Jupiter, as the Juno spacecraft is taking high resolution in situ measurements of the magnetic field and particles which can help to constrain our theories of what causes the powerful X-rays.â€?

Since arriving at Jupiter in 2016, the Juno mission has been re-writing much of what is known about the giant planet, but the spacecraft does not have an X-ray instrument on board. To understand how the X-ray aurora are produced, the team hope to combine the X-ray aurora information gathered using XMM-Newton and Chandra with data collected by Juno as it explores the regions producing Jupiter’s aurora.

One of the theories that Juno may help to prove or disprove is that Jupiter’s auroras form separately when the planet’s magnetic field interacts with the solar wind. The team suspect that the magnetic field lines vibrate, producing waves that carry charged particles towards the poles and these change in speed and direction of travel until they collide with Jupiter’s atmosphere, generating X-ray pulses.

The UCL and Harvard-Smithsonian-led study also involved researchers from Lancaster University, NASA Marshall Space Flight Center, Universite de Liege, Boston University, Southwest Research Institute (SwRI), Jet Propulsion Laboratory, Caltech, MIT and Universidad Pontificia Comillas. It was funded by the Science and Technology Facilities Council (STFC), ESA, the Natural and Environmental Research Council (NERC) and UCL.

Click here to download the paper ‘The independent pulsations of Jupiter’s northern and southern X-ray auroras’ (DOI10.1038/s41550-017-0262-6, Nature Astronomy).

Professor Stefano Moretti from the University of Southampton’s High Energy Physics Group is to be awarded an Honorary Doctorate from Uppsala University in Sweden.

The honour recognises a rich collaboration in both theoretical and experimental high-energy physics between our University and a historic European institution that has spanned two decades and resulted in some 30 research papers.

Stefano will be conferred an Honorary Doctor of Philosophy degree by the Faculty of Science and Technology alongside fellow Southampton academic Professor AbuBakr Bahaj in five new honours announced by Uppsala University this autumn.

The accolade from one of Europe’s oldest and most renowned universities follows in the footsteps of celebrated physicists like Dirac Medallist Roman Jackiw, Clerk Maxwell Professor John Ellis (FRS CBE), CERN Director-General Fabiola Gianotti and Nobel laureate Frank Wilczek.

Stefano says, “I feel honoured, given the prestige of Uppsala University, to be awarded this title and am more determined than ever to continue my research, even if I may never be able to accomplish as much as many of my illustrious predecessors.

“This is a clear recognition of the importance of not only my own work but also of that of any individual who has engaged with me over the years in research: innumerable students, post-docs and colleagues from within Southampton’s High Energy Physics Group. The output of this collaboration has been tremendous and I trust this award is a means of furthering ongoing collaborations into the years to come.â€?

Stefano’s research interests are in collider phenomenology, exploring physics beyond the Standard Model. He is the Director of the NExT Institute, a body bringing together theorists and experimentalists in the process of new physics discovery.

The Honorary Doctorate from Uppsala University opens the door for regular visits and sustained collaboration with local theorists and experimentalists that will enrich high-energy physics research at both institutions.

The academic interactions to date have included grants from the Svenska Institutet, the C.M. Lerici Foundation, The Italian Institute of Culture and currently a Horizon 2020 European Commission award.

Southampton’s High Energy Physics Group studies the most elementary constituents of matter, the basic forces of nature by which they interact and their role in the early Universe. Find out more through the High Energy Physics group website.

Stefano has recently published a book which documents the context of his research, titled Supersymmetry Beyond Minimality: From Theory to Experiment.

A team of scientists led by the University of Southampton has moved a step closer to understanding mysterious cosmic phenomena – known as relativistic jets – that shoot out from the vicinity of black holes.

The ultra-powerful jets, which have been likened to deadly rays fired from Star Wars super-weapon the Death Star, have been observed by measuring how quickly they ‘switch on’ and shine brightly once they are launched.

In a new study published today in Nature Astronomy, an international team of scientists led by Dr Poshak Gandhi show how they used precise multi-wavelength observations of a binary system called V404 Cygni to throw light on this hotly debated phenomenon.

Poshak, an Associate Professor in Southampton’s Department of Physics and Astronomy, says, “Scientists have been observing jets for decades, but are far from understanding how nature creates these mind-bogglingly vast and energetic structures.

“Now, for the first time, we have captured the time delay between the appearance of X-rays and the appearance of optical light in a stellar-mass black hole at the moment jet plasma is activated. This lays to rest the controversy regarding the origin of the optical flashes, and also gives us a critical distance over which jet plasma must have been strongly accelerated to speeds approaching that of light.â€?

The key measurement of this study can be compared in the Star Wars universe to measuring the distance between the surface of the Death Star, where multiple rays of light shoot out, and the point where they converge into a single bright beam.

“But the physics of black hole jets has nothing to do with lasers or the fictional Kyber crystals that power the Death Star,â€? Poshak adds. “Nature has found other ways to power jets. Gravity and magnetic fields play the key roles here, and this is the mechanism we are trying to unravel.â€?

Poshak and his collaborators captured the data in June 2015, when V404 Cygni was observed radiating one of the brightest ‘outbursts’ of light from a black hole ever seen – bright enough to be visible to small telescopes used by amateur astronomers, and energetic enough to tear apart an Earth-like planet if properly focused.

Using telescopes on Earth and in space observing at exactly the same time, they captured a 0.1-second delay between X-ray flares emitted from near the black hole, where the jet forms, and the appearance of visible light flashes, marking the moment when accelerated jet plasma begins to shine. This ‘blink of an eye’ delay was calculated to represent a maximum distance of 19,000 miles (30,000 km), impossible to resolve at the distance of V404 with any current telescope.

As well as Southampton, the research involved the universities of Sheffield, Oxford, Cambridge and Warwick, in the UK, as well as universities in Italy, Spain, France, USA, Canada, Netherlands, Switzerland, India, Germany and the United Arab Emirates.

See an animation which illustrates the cosmic phenomena.