Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists have observed unexpected luminous spots on Jupiter caused by its moon Io

17.03.2008
Besides displaying the most spectacular volcanic activity in the solar system, Io causes auroras on its mother planet that are similar to the Northern Lights on Earth.

The auroral emissions linked to the volcanic moon are called the Io footprint.

From previous studies, researchers had found the Io footprint to be a bright spot that is often followed by other auroral spots. Those spots are typically located downstream relative to a flow of charged particles around the giant planet. Now, a team of planetologists from Belgium and Germany have discovered that Io's footprint can include a faint spot unexpectedly upstream of the main spot.

Each appearance of such a "leading spot" occurs in a distinctive pattern, the scientists say: When the main footprint is preceded by a leading spot in the northern or southern hemisphere of Jupiter, it is also followed by downstream spots in the opposite hemisphere.

"Previously, we only observed downstream spots, but only half of the configurations of Io in the Jovian magnetic field had been studied," says Bertrand Bonfond of the University of Liege in Belgium, who is a member of the team that found the new type of spot. "Now we have the complete picture. The results are surprising because no theory predicted upstream spots."

Like a rock in a stream, Io obstructs the flow of charged particles, or plasma, around Jupiter. As the moon disrupts the flow, it generates powerful plasma waves that blast electrons into Jupiter's atmosphere, creating the auroral spots.

The finding of the leading spot puts all the previous models of the Io footprint into question, Bonfond says. He and his colleagues propose a new interpretation in which beams of electrons travel from one Jovian hemisphere to the other.

The new results were published online on 15 March in Geophysical Research Letters, a journal of the American Geophysical Union. The 16 March print edition of the journal features an image from the study on its cover.

For this latest Io-footprint analysis, Bonfond and his colleagues at Liege and at the University of Cologne in Germany used the Hubble Space Telescope to observe Jupiter in ultraviolet wavelengths.

New insights regarding Io-Jupiter interactions could apply to other situations in which an electrically conductive body--in this case, Io--orbits near a magnetised body, Bonfond says. Such configurations could be very common in the universe. For example, some of the recently discovered exoplanets that orbit stars other than the Sun are thought to be in such configurations with their parent stars.

Our Moon does not create a footprint on Earth because the Moon is not conductive and is also too far from the Earth, Bonfond notes.

In order to test their new theory of how leading and downstream spots form, Bonfond and his colleagues plan further observations of Io's footprint after August 2008. That's when repairs and improvements to the Hubble Space Telescope are scheduled to occur.

Peter Weiss | American Geophysical Union
Further information:
http://www.agu.org
http://www.ulg.ac.be

More articles from Physics and Astronomy:

nachricht From rocks in Colorado, evidence of a 'chaotic solar system'
23.02.2017 | University of Wisconsin-Madison

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Safe glide at total engine failure with ELA-inside

27.02.2017 | Information Technology

Fraunhofer IFAM expands its R&D work on Coatings for protection against corrosion and marine growth

27.02.2017 | Materials Sciences

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>