Violent spacequakes shake Earth from above
2010 08 03

From: YahooNews.ca


Like an earthquake in space, so-called spacequakes are temblors in Earth’s magnetic field caused by plasma flying off the sun that could help generate the colorful auroras that dance high in Earth’s atmosphere, a new study suggests.

While felt most strongly in Earth orbit, these quakes can also reach all the way down to the surface of Earth itself.

"Magnetic reverberations have been detected at ground stations all around the globe, much like seismic detectors measure a large earthquake," said Vassilis Angelopoulos of UCLA, principle investigator of NASA’s THEMIS spacecraft.

And these rumbles can pack a punch.

"The total energy in a spacequake can rival that of a magnitude 5 or 6 earthquake," according to Evgeny Panov of the Space Research Institute in Austria. Panov is first author of a paper reporting the results of a study on spacequakes in the April 2010 issue of Geophysical Research Letters. [Illustration: Spacequake in action.]

Spacequakes aren’t the only unearthly temblors around. Scientists have also discovered starquakes (violent trembling inside stars), moonquakes and asteroid quakes (seismic tremors on the surface of the moon and asteroids, respectively). In fact, Earth can actually stimulate asteroidquakes when wayward space rocks fly too close to our planet.

In 2007, THEMIS discovered the precursors of spacequakes. The action begins in Earth’s magnetic tail, which is stretched out like a windsock by the million-miles-per-hour solar wind. Sometimes the tail can become so stretched and tension-filled, it snaps back like an over-torqued rubber band.

Solar wind plasma trapped in the tail hurtles toward Earth. On more than one occasion, the five THEMIS spacecraft were in the line of fire when these "plasma jets" swept by. Clearly, the jets were going to hit Earth. But what would happen then? The fleet moved closer to the planet to find out.

"Now we know," said THEMIS project scientist David Sibeck of NASA’s Goddard Space Flight Center in Greenbelt, Md. "Plasma jets trigger spacequakes."

According to THEMIS, the jets crash into the geomagnetic field some 18,600 miles (30,000 km) above Earth’s equator. The impact sets off a rebounding process, in which the incoming plasma actually bounces up and down on the reverberating magnetic field, akin to a tennis ball bouncing up and down on a carpeted floor. The first bounce is a big one, followed by bounces of decreasing amplitude as energy is dissipated in the carpet.

"We’ve long suspected that something like this was happening," Sibeck said. "By observing the process in situ, however, THEMIS has discovered something new and surprising."

The surprise is plasma vortices, huge whirls of magnetized gas as wide as Earth itself, spinning on the verge of the quaking magnetic field.

The tails of these vortices are thought to funnel particles into Earth’s atmosphere, sparking colorful auroras that dance over the sky.


Article from: ca.news.yahoo.com



Related Articles
Themis: Greek Titan - Wikipedia
NASA: THEMIS Mission
NASA Chile Quake Changed Space Time Axis Setting up Pole Shift (Video)
Spacequake Rumbles Near Earth (Video)
Antarctica Experiment Discovers Puzzling Space Ray Pattern
Aurora Australis Observed from the International Space Station
Space fireball lights up night sky in Wisconsin (Video)
Is there a secret war being waged in space? (Video)
Huge Spherical Objects in the Corona of the Sun - Shot by NASA’s Stereo Spacecraft


Latest News from our Front Page

US Silent on Psychologists Role in CIA’s Tortures: Doctors
2014-12-20 21:53
Physicians for Human Rights had not received any response from the US Federal Commission to their call to investigate the role of health professionals in CIA’s torture program, Deputy Director of the organization told Sputnik. December 19 (Sputnik) — US government has not responded to calls to prosecute doctors, who participated in CIA torture program, the Deputy Director of Communications for ...
Ziolebrities: Simon Cowell donates £100,000 to Israeli soldiers to please pregnant jewish girlfriend Lauren Silverman
2014-12-20 21:00
Cowell, 54, is also planning a secret trip to Israel soon as he embraces the Jewish faith of Silverman, 36 Gala: Billionaire Haim Saban with Cowell Simon Cowell has publicly donated nearly £100,000 in support of the Israeli army. The X Factor boss pledged the cash to the Friends of the Israel Defense Forces at a US fund-raiser in Beverly Hills. The lavish gala ...
Former Chief Security Officer for NewsCorp: N. Koreans Not Behind Sony Hack, Interview Leak
2014-12-20 2:17
Hemanshu Nigam, a former federal prosecutor and former chief security officer for NewsCorp/Fox studios, says North Korea isn’t behind the Sony Hack. Nigam gave several bullet points for why the hack was likely an inside job. Attack code borrowed from a previous attack on Seoul, that’s why it’s in Korean. Private hackers typically borrow malicious code from other hackers.Nations state attacks follow ...
Sony Fires Back at Obama: Actually We Did Call the White House – Several Times
2014-12-20 2:13
Sony fired back at Obama after the press conference saying they had several conversations with the Obama White House before and after the movie was canceled. Via The Hollywood Reporter: After President Obama criticized Sony for its decision to cancel The Interview's release after theater chains decided not to show the film, the studio has issued a statement elaborating on the move. “The ...
The Bankster International
2014-12-20 1:55
Geopolitical analysis, the art of explaining power relationships through the prism of impersonal geography, can be a helpful tool for observers of the Great Game – but it also has its limitations. A case in point is the renewed US-Russia confrontation. Think tanks and policy insiders easily sell the narrative that from the dark days of the Cold War to ...
More News »