The planet Jupiter has spectacular rings of auroras around each pole but until now scientists have not been able to explain how they form. All auroras are caused by energetic charged particles crashing into the top of the atmosphere and making it glow. In the Earth’s auroras, these particles come from the Sun in a flow of charged particles known as the solar wind. But this can’t account for Jupiter’s auroras because the solar wind does not reach to the region where the brightest are found. Space physicists from the University of Leicester have now proposed a new theory of how Jupiter’s auroras are formed.
An enormous disk of plasma gas rotates around Jupiter, flowing outwards from the moon Io. They believe that a large-scale electric current system (stream of charged particles) flows between the planet’s upper atmosphere and this disk of gas. They have also calculated that in order for such large currents to flow between the atmosphere and the disk, electrons must be strongly accelerated between these regions, causing the bright ring of auroras around each pole when they hit the top of the atmosphere and make it glow.
Professor Stan Cowley, of the University of Leicester said: "The force associated with this electric current causes the plasma gas to spin at the same rate as the planet as it flows outwards. Our calculations suggest that the total current in this giant circuit is 100 million amps. The power transferred from the atmosphere to the plasma disk is about a thousand million megawatts or about 20,000 times the peak electricity demand in the UK!"
Julia Maddock | alphagalileo
Neutron star merger directly observed for the first time
17.10.2017 | University of Maryland
Breaking: the first light from two neutron stars merging
17.10.2017 | American Association for the Advancement of Science
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
18.10.2017 | Health and Medicine
18.10.2017 | Life Sciences
17.10.2017 | Life Sciences