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Fraser
2004-Aug-12, 10:14 PM
SUMMARY: The European Space Agency's Cluster spacecraft have helped answer a 17-year mystery about how the magnetosphere, a magnetic bubble that surrounds the Earth, keeps filling up with electrified gases, when it should be acting as a barrier to keep them out. The four Cluster spacecraft found huge swirling vortices of gas at the outer edges of the magnetosphere caused by interacting flows of solar wind. As they collapse, they force material into the magnetosphere, filling it up.

What do you think about this story? Post your comments below.

om@umr.edu
2004-Aug-12, 10:23 PM
Thanks, Fraser, for news on this topic.

Understanding Earth's magnetosphere may be of general interest, since fluctuations in the magnetosphere could quickly and drastically alter Earth's climate.

With kind regards,

Oliver
http://www.umr.edu/~om

jitte
2004-Aug-13, 01:32 AM
How does this relate to the plasmasphere and what's known as the plasmatail?

Guest
2004-Aug-13, 08:48 AM
Cool it's a cluster of space craft..this must bring the crft's ability to the maximum

the day we launch fleets of ships into space for exploration and study should be a great day

lswinford
2004-Aug-13, 01:36 PM
I agree, guest, I've mused at a discussion on our solar bubble and thought it would be good to send out several relatively simple probes to help measure and define the boundaries of our solar system. I wonder if the planets also cause instabilities in the solar winds that cause similar effects in our solar system's boundary zones. It would be interesting if the background radiation of this part of the galaxy were higher and our solar winds were deflecting things like our magnetosphere does against the sun. But then we'd have to send, as in this local case, a bunch of probes to be definitive. Of course, a bunch of people would be saying, "while you've got something going out there could you add a ---" and as each probe gets burdened with more equipment then the cost goes up and their numbers go down. Oh, well....

csarridge
2004-Aug-24, 11:32 PM
Hello all,

Firstly to jitte's questions; the plasmasphere is a region inside a magnetosphere which contains cool dense plasma originating from the ionospheric region of the Earth's upper atmosphere. I believe the plasmatail you mention is the Earth's magnetotail. The tail region is downstream of the Earth in the solar wind flow and is where the solar wind pulls the Earth's magnetic field away from the Earth. There is a nice schematic of the magnetosphere here which illustrates the situation nicely:

http://www.irf.se/rpg/science/picts/Magnetosphere.gif

Secondly, understanding the terrestrial magnetosphere is very important to understanding climate since it acts as an interface between the sun and the earth's atmosphere - not particularly with respect to light and heat, but in terms of solar wind activity.

It is also interesting to note that the solar system has it's own magnetosphere. This is called the heliosphere and the boundaries of this magnetic bubble, called the heliopause is where the pressure of the solar wind flowing away from the sun is balanced by the flow of gas and also by light (radiation pressure) in the interstellar medium. The Voyager spacecraft are presently on their way out of the solar system and are due to encounter this boundary in the next decade. They have already seen evidence of solar wind pulses passing over the spacecraft and then being detected again as they reflect off the heliopause and travel back into the solar system.

Regards,
Chris

lswinford
2004-Aug-25, 06:35 PM
Heliopause, right. So its possibly a magnetic line that defines it. Interesting. By the way, I've also wondered about the tropopause (sp?), that upper boundary of the troposphere that gives tall cumulous (drat, my spelling is awful today) clouds that 'anvil' effect. That's not reported as a magnetic effect. And there is a phenomenon in the Amazon river where water from one tributary doesn't mix well with the main stream for reasons also unclear. What else would cause that heliopause phenomena? Perhaps some distant gravity/solar pressure equilibrium zone? A chemical cohesion spread thin by angular momentum of fresh particles from the solar wind and flare ejecta? And if its magnetic, as the sun keeps boiling out mass in its ongoing solar wind are there currents and eddies, does the matter flow back along its arching lines to the solar poles?