Cluster spacecraft detects elusive space wind (w/ Video)

Jul 02, 2013

A new study provides the first conclusive proof of the existence of a space wind first proposed theoretically over 20 years ago. By analysing data from the European Space Agency's Cluster spacecraft, researcher Iannis Dandouras detected this plasmaspheric wind, so-called because it contributes to the loss of material from the plasmasphere, a donut-shaped region extending above the Earth's atmosphere. The results are published today in Annales Geophysicae, a journal of the European Geosciences Union (EGU).

"After long scrutiny of the data, there it was, a slow but steady wind, releasing about 1 kg of plasma every second into the outer : this corresponds to almost 90 tonnes every day. It was definitely one of the nicest surprises I've ever had!" said Dandouras of the Research Institute in Astrophysics and Planetology in Toulouse, France.

The plasmasphere is a region filled with charged particles that takes up the inner part of the Earth's magnetosphere, which is dominated by the planet's .

To detect the wind, Dandouras analysed the properties of these charged particles, using information collected in the plasmasphere by ESA's Cluster spacecraft. Further, he developed a filtering technique to eliminate noise sources and to look for plasma motion along the radial direction, either directed at the Earth or .

As detailed in the new Annales Geophysicae study, the data showed a steady and persistent wind carrying about a kilo of the plasmasphere's material outwards each second at a speed of over 5,000 km/h. This plasma motion was present at all times, even when the Earth's magnetic field was not being disturbed by coming from the Sun.

This video is not supported by your browser at this time.
This animation shows the Earth's plasmasphere -- the innermost part of our planet's magnetosphere -- and the plasmaspheric wind, an outward flow of charged particles. The doughnut-shaped plasmasphere is centred around the Earth's equator and rotates along with it. The steady plasmaspheric wind continuously transfers material from the plasmasphere into the magnetosphere, releasing about 1 kg of plasma every second -- almost 90 tonnes a day -- into the outer magnetosphere. Credit: ESA/ATG medialab

Researchers predicted a space wind with these properties over 20 years ago: it is the result of an imbalance between the various forces that govern plasma motion. But direct detection eluded observation until now.

"The plasmaspheric wind is a weak phenomenon, requiring for its detection sensitive instrumentation and detailed measurements of the particles in the plasmasphere and the way they move," explains Dandouras, who is also the vice-president of the EGU Planetary and Solar System Sciences Division.

The wind contributes to the loss of material from the Earth's top atmospheric layer and, at the same time, is a source of plasma for the outer magnetosphere above it. Dandouras explains: "The plasmaspheric wind is an important element in the mass budget of the plasmasphere, and has implications on how long it takes to refill this region after it is eroded following a disturbance of the planet's magnetic field. Due to the plasmaspheric wind, supplying plasma – from the upper atmosphere below it – to refill the plasmasphere is like pouring matter into a leaky container."

The plasmasphere, the most important plasma reservoir inside the magnetosphere, plays a crucial role in governing the dynamics of the Earth's radiation belts. These present a radiation hazard to satellites and to astronauts travelling through them. The plasmasphere's material is also responsible for introducing a delay in the propagation of GPS signals passing through it.

"Understanding the various source and loss mechanisms of plasmaspheric material, and their dependence on the geomagnetic activity conditions, is thus essential for understanding the dynamics of the magnetosphere, and also for understanding the underlying physical mechanisms of some space weather phenomena," says Dandouras.

Michael Pinnock, Editor-in-Chief of Annales Geophysicae recognises the importance of the new result. "It is a very nice proof of the existence of the plasmaspheric wind. It's a significant step forward in validating the theory. Models of the plasmasphere, whether for research purposes or space weather applications (e.g. GPS signal propagation) should now take this phenomenon into account," he wrote in an email.

Similar winds could exist around other planets, providing a way for them to lose atmospheric material into space. Atmospheric escape plays a role in shaping a planet's atmosphere and, hence, its habitability.

Explore further: Mercury's magnetic field tells scientists how its interior is different from Earth's

More information: This research is presented in the paper 'Detection of a plasmaspheric wind in the Earth's magnetosphere by the Cluster spacecraft' to appear in the EGU open access journal Annales Geophysicae on 2 July 2013: www.ann-geophys.net/31/1143/20… eo-31-1143-2013.html

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User comments : 9

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Osiris1
1.6 / 5 (7) Jul 02, 2013
How is this related to the solar wind? Does not say so in the article.
Fleetfoot
5 / 5 (6) Jul 02, 2013
How is this related to the solar wind?


It isn't, it's an entirely separate flow.
Maggnus
5 / 5 (8) Jul 03, 2013
oh oh the headline says "elusive space wind" *****Ducks, looks around***** cantdrive be coming!!! He can't resist a headline like that!
Fleetfoot
5 / 5 (8) Jul 03, 2013
oh oh the headline says "elusive space wind" *****Ducks, looks around***** cantdrive be coming!!! He can't resist a headline like that!


He'll probably rise to your bait but maybe not, facts like this expose his claim that current science doesn't account take account of plasma effects:

"Researchers predicted a space wind with these properties over 20 years ago: it is the result of an imbalance between the various forces that govern plasma motion. But direct detection eluded observation until now."
cantdrive85
1 / 5 (16) Jul 03, 2013
"But direct detection eluded observation until now."


So the observation of plasma phenomenon are difficult? Especially difficult unless you are looking specifically for that which you expect.

facts like this expose his claim that current science doesn't account take account of plasma effects

Nothing more needs to be said other than "magnetic reconnection", current pseudo-science accounts for some plasma effects. I'm just waiting for current real science to account for real plasma effects.

Requiem
3.4 / 5 (10) Jul 03, 2013
I disagree cantdrive85. My opinion on the matter is that nothing more needs to be said than "unicorns and rainbows", current pseudo-science accounts for some unicorn and/or rainbow effects. I'm just waiting for current real science to account for them.

I'm not sure exactly why I'm waiting for that, or what I expect to happen when they make the big unicorn and rainbow discovery. Sweet vindication, I suppose. That big meany Requiem on physorg will be crying in his cheerios when he sees that, he won't be talking about how taking shots in the dark is still stupid.
Fleetfoot
5 / 5 (7) Jul 03, 2013
"But direct detection eluded observation until now."


So the observation of plasma phenomenon are difficult?


Observing a transfer rate of 1 kg of plasma per second spread over the whole plasmasphere is difficult, it's a very small flow and occurs in the presence of lots of other effects.

Especially difficult unless you are looking specifically for that which you expect.


Pardon? Do you think they were carefully looking for something they didn't expect?
ElijahTruth
1 / 5 (2) Jul 28, 2013
To see the only website to correctly prophesy these major record setting disturbances in the Heavens such as the record sun flare and whirlwind on the suns surface and Too view evidence that God's Science has finished His Mystery Rev:10:7 go to the websites now mentioned below in past yahoo news/facebook commentary pasted below... It has Begun .. Our Lord's science has proved His mystery and instead His children of Science deny Him while reaping the benefits of His delivered Knowledge! For evidence that He and He alone brought forth Science go to the Proof in the news and science page, and the Targum page and the Proof of His healing in painting and verse page on the website at google search of Adam and Eve seed gathering Ministry!

Also on the Prophecy and the Signs page are the prewritten news events of this day prewritten three years ago and some more, and are now falling each week, such as the Japan quake and tidal wave, and the DC/Virginia Beach Virginia quake... It has Begun
Fleetfoot
5 / 5 (1) Jul 28, 2013
To see the only website to correctly prophesy these major record setting disturbances ...


Clueless rubbish, this isn't even a "disturbance", never mind "major" or "record setting", it is a continuous background flow which has been known about for decades and no doubt running continuously for the 4.5 billion year existence of the planet.