Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Satellites see largest jet of particles created between Sun and Earth

13.01.2006


A flotilla of space-weather satellites – ESA’s Cluster and NASA’s ACE and Wind - observed for the first time steady large-scale jets of charged particles in the solar wind between the Sun and Earth.



When such huge jets of particles impact on Earth’s magnetic shield, they could cause powerful magnetic storms on our planet. Understanding the mechanism behind these phenomena - called ‘magnetic reconnection’ – is also fundamental to many explosive phenomena, such as solar flares, powerful gamma-ray bursts from ‘magnetars’ (dead stars noted for their extreme magnetic fields) and laboratory nuclear fusion.

Magnetic reconnection is a natural process by which the energy of magnetic field is converted into particle energy and by which, for instance, solar particles can penetrate through Earth’s magnetic shield, sometimes causing magnetic storms as well as beautiful ‘aurorae’, or polar lights.


Magnetic reconnection takes place when sheets of oppositely directed magnetic field get pressed together. In doing so, the sheets cross to form an X-shape that is then temporarily broken to form a new magnetic line geometry.

The creation of a different geometry induces jets of electrically charged particles and also allows solar material to pass through newly created ‘cracks’ in the previously impenetrable magnetic field configuration.

So far, magnetic reconnection events have been almost exclusively reported in Earth’s magnetosphere. This is the natural magnetic shield surrounding Earth. It is composed of magnetic field lines generated by our planet, and defends us from the continuous flow of charged particles that make up the solar wind by deflecting them away from Earth.

However, when the interplanetary magnetic field lines carried by the solar wind happen to be in the opposite orientation to Earth’s magnetic field lines, reconnection is triggered and solar material can break through Earth’s shield.

Previous reconnection events measured in Earth’s magnetosphere suggested that the phenomenon was intrinsically random and patchy in nature, extending not more than a few tens thousand kilometres.

However, a broader picture of magnetic reconnection emerged when six spacecraft – the four Cluster and the ACE and Wind satellites – were flying in the solar wind outside Earth’s magnetosphere, in sunward direction, on 2 February 2002.

During a time span of about two and a half hours, all spacecraft observed in sequence a single huge stream, or jet, of charged particles, up to 2.5 million kilometres (390 Earth radii) wide, caused by the largest reconnection event ever measured.

“If the observed reconnection were patchy, one or more spacecraft most likely would have not encountered an accelerated flow of particles,” says Tai Phan, from the University of California, Berkeley, USA, lead author of the results.

“Furthermore, patchy and random reconnection events would have resulted in different spacecraft detecting jets directed in different directions, which was not the case.”

The fact that the spacecraft detected the jet for more than two hours, also implies that the reconnection must have been almost steady over at least that timespan. Another 27 reconnection events of large magnitude – with the associated jets - were identified by ACE and Wind, four of which extended more than 100 Earth radii, or 650 000 kilometres.

Thanks to these additional data, scientists could conclude that reconnection in the solar wind is to be looked at as an extended and steady phenomenon.

Magnetic reconnection, responsible for transport of mass and energy across Earth’s magnetic defences, is a central issue in space physics. Consequences of this transport can be strong magnetic storms that have the potential to severely impair critical technology infrastructure.

Potential damage includes widespread power failures, pipeline corrosion, shutdown of cable systems, satellite failures, inaccurate GPS positioning and disturbed radio navigation.

Understanding magnetic reconnection is also fundamental when having to control magnetic fields and particles energy during nuclear experiments in laboratories. One of the keys to producing ‘clean’ nuclear energy (nuclear fusion) is making sure that reconnection phenomena do not take place, as they could cause powerful and dangerous jets of particles to be released uncontrolled.

“Only with co-ordinated measurements by spacecraft like Cluster, ACE and Wind can we probe the near-Earth space environment with unprecedented detail and in three dimensions,” continued Phan.

“This is the only natural laboratory were the physics of plasma and the magnetic phenomena that drive it can be studied in situ, paving the way to many applications,” he concluded.

Philippe Escoubet | alfa
Further information:
http://www.esa.int/esaSC/SEMAFQG23IE_index_0.html

More articles from Earth Sciences:

nachricht Monitoring lava lake levels in Congo volcano
16.05.2018 | Seismological Society of America

nachricht Ice stream draining Greenland Ice Sheet sensitive to changes over past 45,000 years
14.05.2018 | Oregon State University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

Im Focus: Computer-Designed Customized Regenerative Heart Valves

Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.

Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...

Im Focus: Light-induced superconductivity under high pressure

A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.

Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Supersonic waves may help electronics beat the heat

18.05.2018 | Power and Electrical Engineering

Keeping a Close Eye on Ice Loss

18.05.2018 | Information Technology

CrowdWater: An App for Flood Research

18.05.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>