Saturday, December 22, 2007

Strange Weather in space.-The discovery of Ion Plumes.

Something abnormal is disturbing the electrical equilibrium in the Atmospheric Space(the Ionosphere to be specific) above Africa of late. Just last week scientists from around the world gathered together at Addis Ababa(the capital of Ethiopia) to discuss what could be doing this.-(This was called the “Africa Space Weather Workshop, November 12th 2007,” organized primarily under the auspices of the International Heliophysical Year,2007, which is being organized symbolically on the Golden Jubilee of the International Geophysical Year,1957).


They ended up with a proper name for this strange phenomenon they had seen of late.-They called it an Ion Plume!


This strange new phenomenon that we have now begun to call an ion plume is basically a newly discovered form of space weather. The plumes are somewhat like smoke billowing out of a factory smokestack—except instead of ordinary ash and dust, ion plumes are made of electrified gas (or actually better decribed as IONIZED gas, to maintain the lingo) floating so high above the ground that they come in contact with space itself.They appear during geomagnetic storms (basically Coronal bursts or CMEs as we otherwise call them) and they can interfere with satellite transmissions, airline navigation and radio communications, i.e. to say basically any mode of transmission where the accuracy of the information/data that is being encoded in electromagnetic waves is being made use of.

These Ion plumes that we are intending to monitor(listen in on & subsequently track) using receivers(generally GPS is used) inhabit a layer of the Earth's atmosphere called the Ionosphere, a broad region extending from 85 km to 600 km above ground level to outer Space, where ultraviolet radiation from the sun knocks electrons off atoms and molecules, creating a layer of ionized gas or plasma surrounding our entire planet. As ham(amateur radio relay) radio operators have known for nearly a century, the ionosphere can bend, distort, reflect and even absorb radio waves. Plumes amplify these effects.Thus exhibiting characteristics that allow for their detection.


These plumes were basically first detected due to the effect they produced on GPS signals.This led to their discovery not too long back.– couple of years to be precise as GPS was not in widespread civilian use before that.
As one would expect, due to the abundance of GPS receivers in the North American continent, this was where they were first detected.


But now, if you notice carefully, there is still something critical missing in my description of this Plume phenomenon in my post.-While I gave the analogy of smoke billowing out of a smokestack, I have still not been able to give you a description of the smokestack.In other words, you've seen the smoke, but where is the smokestack that I referred to previously?-The search to explain this anomaly, that has not yet been completely explained even by the scientists, is leading a whole lot of scientists to Africa.-As I mentioned before, this weird form of space weather that was unknown to us before has been observed in abundance of late over the continental landmass of Africa.

Now as it turns out, most of the scientists who have been working on this have now begun to believe that the source of the plumes is near the Earth's magnetic equator.This includes one particularly interesting Bengali girl from Calcutta,India whose research work summary on the subject I directly looked through while preparing my post.She is NASA heliophysicist Lika Guhathakurta (otherwise also called “Madhulika” affectionately by those in the astronomy community).(who is also attending the Workshop I previously described).When asked, why Africa?, she quite frankly explains to everyone that Africa is a great place to check this possibility(the theory of origin of the plumes at the Earth’s magnetic Equator) because the magnetic equator passes directly over the sub-Sahara.But there is a problem of practicality in doing this as there are just not enough sensors in Africa to study this phenomenon. -The sensor of choice is, as indicated by experience from incidents that took place before, the dual-frequency GPS receiver.However, unlike their wealthier counterparts in North America, the Africans have only a few dozen dual frequency GPS receivers in comparison to the thousands of them presently in use in the US alone.And fewer still in sub Saharan Africa. It would not be stretching it too far to say that the purpose of the abovementioned workshop itself was to familiarize the African space scientists with this plume phenomenon and thus encourage them to do the groundwork for a continent-wide GPS network in the hopes of deploying hundreds of thousands of receivers in sub-Saharan Africa in the years to come.(In other words, engineer a revolution in GPS receiver usage in Africa.)

Presently only North America is equipped enough to have a well-mapped Ionosphere in realtime (note:when we say realtime here, we mean = “live”).The NOAA(National Oceanographic and Atmospheric Administration) posts new images every quarter of an hour at their website at http://www.swpc.noaa.gov/ustec . However, the organizers of the workshop have set an aim for themselves that in the next five years they too shall begin making such realtime maps of the ionosphere over Africa.

Now having explained how Africa fits into the bigger picture if you were to begin to wonder why does it have to be Africa only where we have to observe this phenomenon?(because Africa itself has barely any infrastructure for research and observation on this scale!).Why not just wait for the next Ion Plume over a somewhat more wealthier region of the world which might also be on the magnetic equator?! i.e. if you were to wonder, just how important Africa is to the study of this phenomenon.

Then all you have to do is consider the list of organizations who have joined forces to sponsor the Africa Space Weather Workshop: NASA, the NOAA, the National Science Foundation(NSF), the European Office of Aerospace Research and Development (EOARD), the International Center for Theoretical Physics (ICTP), and many others.It is widely understood(or better said, Accepted,) that Africa is the key to the puzzle as it is the only place of it’s sort located so perfectly on the Magnetic Equator. Therein lies the dilemma so beautifully poised to us by Mother Nature.

Thus as it turns out Africa is “plasma incognita” as of now.

But it shall not be so for too long. Stay tuned!(specially all the HAMs!)

Surjodeb Basu .(/Dev/Dave)
(22/11/2007)



I am attaching here a picture of a typical example of an Ion Plume.This is the plume of Nov. 20, 2003:(It was observed over North America.-I hav attached the whole description below)

My Description of the above photo: A plume of excess electron density that was observed over North America on Nov. 20, 2003.The plume was discovered and mapped by its effect on GPS signals alone.I got this image from the NASA archives, courtesy of Anthea Coster and John Foster of MIT.

Two days before this map was made, an explosion on the sun had hurled a cloud of magnetized gas—a CME—towards Earth.The plume formed when the CME hit, triggering a strong geomagnetic storm.The plume consisted of ionized air at high altitude moving from Florida to Canada at a speed of 1 km/s (that would be aprrox 2200 mph).

Pls note: 4 this article i hav used as my src reference material that was mostly in the form of Press Releases by the IHY organisation.Any other data that i needed i researched by obtaining from the internet any interviews of people associated with IHY(Mostly NASA people).

ps-the author would like to acknowledge that the writing of this article was inspired largely due to the association of Prof.Madhulika Guhathakurta with research into this new discovery.

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