Feeds

Wobbly sun causes plasma jets

127-year-old mystery solved

  • alert
  • submit to reddit

Application security programs and practises

A group of scientists has come up with a new explanation for the origins of spicules - jets of plasma that shoot up from the solar surface at speeds of around 90,000 kilometres per hour: the solar matter is propelled into space by sound waves entering the solar atmosphere.

Using observational data from two satellites (TRACE and SOHO) and an the Swedish Solar optical telescope, scientists at Sheffield university and the Lockheed Martin Solar and Astrophysics lab, have determined that the jets occur periodically, about every five minutes or so.

Professor Erdélyi von Fáy-Siebenbürgen then developed a computer simulation of the events, incorporating the effects of compression waves, or sounds waves, in the sun. He explained that the compression waves are most likely caused by two things: the oscillation of the sun itself, and convection cells - areas of rising and falling solar matter. Convection cells on Earth cause thermals, breezes, thunderstorms and other weather patterns. In the sun, they cause compression waves..

The compression waves are usually damped before they reach the solar atmosphere, von Fáy-Siebenbürgen said, but occasionally they get through. When this happens, the compression of the atmosphere forms a shock wave, propelling matter upwards in the form of a plasma jet. The research solves an astrophysical puzzle that has baffled scientists for over 120 years since the spicules were first discovered.

His model produced jets at virtually identical intervals: "I would say it is around 99 per cent accurate," he told The Register today. "We were very surprised by the accuracy of the model. It is something we are very proud of," he said.

Although relatively small compared to full scale solar flares, spicules are interesting for the same reasons: they may contribute to the solar wind. This flow of highly charged particles causes the Aurorae Borealis and Australis, but can also knock out satellites and even bring down electrical systems on Earth during particularly vigarous solar storms. ®

Related stories

Mission to map the Aurorae launches 26 July
ESA to probe Earth's magnetic field
In the event of nuclear attack, your data is safe

Build a business case: developing custom apps

More from The Register

next story
Asteroid's DINO KILLING SPREE just bad luck – boffins
Sauricide WASN'T inevitable, reckon scientists
BEST BATTERY EVER: All lithium, all the time, plus a dash of carbon nano-stuff
We have found the Holy Grail (of batteries) - boffins
Just TWO climate committee MPs contradict IPCC: The two with SCIENCE degrees
'Greenhouse effect is real, but as for the rest of it ...'
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
Famous 'Dish' radio telescope to be emptied in budget crisis: CSIRO
Radio astronomy suffering to protect Square Kilometre Array
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Securing Web Applications Made Simple and Scalable
Learn how automated security testing can provide a simple and scalable way to protect your web applications.