. | . |
Scientists solve 40-year mystery over Jupiter's X-ray aurora by Staff Writers London, UK (SPX) Jul 12, 2021
A research team co-led by UCL (University College London) has solved a decades-old mystery as to how Jupiter produces a spectacular burst of X-rays every few minutes. The X-rays are part of Jupiter's aurora - bursts of visible and invisible light that occur when charged particles interact with the planet's atmosphere. A similar phenomenon occurs on Earth, creating the northern lights, but Jupiter's is much more powerful, releasing hundreds of gigawatts of energy, enough to briefly power all of human civilisation*. In a new study, published in Science Advances, researchers combined close-up observations of Jupiter's environment by NASA's satellite Juno, which is currently orbiting the planet, with simultaneous X-ray measurements from the European Space Agency's XMM-Newton observatory (which is in Earth's own orbit). The research team, led by UCL and the Chinese Academy of Sciences, discovered that X-ray flares were triggered by periodic vibrations of Jupiter's magnetic field lines. These vibrations create waves of plasma (ionised gas) that send heavy ion particles "surfing" along magnetic field lines until they smash into the planet's atmosphere, releasing energy in the form of X-rays. Co-lead author Dr William Dunn (UCL Mullard Space Science Laboratory) said: "We have seen Jupiter producing X-ray aurora for four decades, but we didn't know how this happened. We only knew they were produced when ions crashed into the planet's atmosphere. "Now we know these ions are transported by plasma waves - an explanation that has not been proposed before, even though a similar process produces Earth's own aurora. It could, therefore, be a universal phenomenon, present across many different environments in space." X-ray auroras occur at Jupiter's north and south poles, often with clockwork regularity - during this observation Jupiter was producing bursts of X-rays every 27 minutes. The charged ion particles that hit the atmosphere originate from volcanic gas pouring into space from giant volcanoes on Jupiter's moon, Io. This gas becomes ionised (its atoms are stripped free of electrons) due to collisions in Jupiter's immediate environment, forming a donut of plasma that encircles the planet. Co-lead author Dr Zhonghua Yao (Chinese Academy of Sciences, Beijing) said: "Now we have identified this fundamental process, there is a wealth of possibilities for where it could be studied next. Similar processes likely occur around Saturn, Uranus, Neptune and probably exoplanets as well, with different kinds of charged particles 'surfing' the waves." Co-author Professor Graziella Branduardi-Raymont (UCL Mullard Space Science Laboratory) said: "X-rays are typically produced by extremely powerful and violent phenomena such as black holes and neutron stars, so it seems strange that mere planets produce them too. "We can never visit black holes, as they are beyond space travel, but Jupiter is on our doorstep. With the arrival of the satellite Juno into Jupiter's orbit, astronomers now have a fantastic opportunity to study an environment that produces X-rays up close." For the new study, researchers analysed observations of Jupiter and its surrounding environment carried out continuously over a 26-hour period by the Juno and XMM-Newton satellites. They found a clear correlation between waves in the plasma detected by Juno and X-ray auroral flares at Jupiter's north pole recorded by X-MM Newton. They then used computer modelling to confirm that the waves would drive the heavy particles towards Jupiter's atmosphere. Why the magnetic field lines vibrate periodically is unclear, but the vibration may result from interactions with the solar wind or from high-speed plasma flows within Jupiter's magnetosphere. Jupiter's magnetic field is extremely strong - about 20,000 times as strong as Earth's - and therefore its magnetosphere, the area controlled by this magnetic field, is extremely large. If it was visible in the night sky, it would cover a region several times the size of our moon. The work was supported by the Chinese Academy of Sciences, the National Natural Science Foundation of China, and the UK's Science and Technology Facilities Council (STFC), Royal Society, and Natural Environment Research Council, as well as ESA and NASA. Jupiter's X-ray aurora alone releases about a gigawatt, equivalent to what one power station might produce over a period of days.
Research Report: Revealing the source of Jupiter's x-ray auroral flares
Next stop Jupiter as country's interplanetary ambitions grow Beijing (XNA) Jun 16, 2021 Barely a month after China landed its first rover on Mars, the country's scientists already have plans to explore Jupiter, the largest planet in our Solar System. Zhang Rongqiao, an official at the China National Space Administration and chief planner of the Tianwen 1 Mars mission, told reporters at a news conference at his administration's Beijing headquarters on Saturday that China will not be content with the success of its first Mars expedition, but will continue its interplanetary adventures. ... read more
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |