Slashdot Mirror
Solar Wind Rips Up Martian Atmosphere
IHateEverybody writes "Scientists have found evidence that the solar wind is ripping off chunks of the Martian atmosphere, which could possibly explain why Mars has such a thin atmosphere today. The chunks are being ripped up along 'magnetic umbrellas,' which are bubbles of magnetic fields which rise from the ground and extend above the Martian atmosphere. This is surprising because scientists previously thought that these magnetic umbrellas protected the Martian atmosphere. Now it looks like exactly the opposite might be true."
A magnetic field.
As I understand it, the Earth's magnetic field is healthy and extends up past the bulk of our atmosphere. The pushing from the solar wind deforms our atmosphere, but any ripples or other magnetic eddies are considerably smaller and that possible "ripping" of an Earth eddy would take place pretty far above the planet. I might guess that the Earth's magnetic field is consistent enough to prevent any large eddies from forming in the first place.
This says different: http://www.space.com/scienceastronomy/mars_core_030306.html
To be slightly more specific, the magnetic field of Earth has been oscillating all the time, even disappearing for some time on numerous occasions. And Earth's atmosphere is still here, so perhaps we do not have to worry too much about this (as for radiation effects on living beings including humans, however, that might be an entirely different question).
Ezekiel 23:20
well, we know for a fact it occured quie a few times before, and our atmosphere is still here.
Wikipedia describes it quite well:
"Because the magnetic field has never been observed to reverse by humans with instrumentation, and the mechanism of field generation is not well understood, it is difficult to say what the characteristics of the magnetic field might be leading up to such a reversal. Some speculate that a greatly diminished magnetic field during a reversal period will expose the surface of the earth to a substantial and potentially damaging increase in cosmic radiation. However, Homo erectus and their ancestors certainly survived many previous reversals. There is no uncontested evidence that a magnetic field reversal has ever caused any biological extinctions. A possible explanation is that the solar wind may induce a sufficient magnetic field in the Earth's ionosphere to shield the surface from energetic particles even in the absence of the Earth's normal magnetic field [8].
Although the inspection of past reversals does not indicate biological extinctions, present society with its reliance on electricity and electromagnetic effects (e.g. radio, satellite communications) may be vulnerable to technological disruptions in the event of a full field reversal."
if (!signature) { throw std::runtime_error("No sig!"); }
The core of the earth will cool long before the sun goes red dwarf.
I think you mean red giant (red dwarf is a main stage star - our sun is a yellow dwarf that will eventually become red giant then a white dwarf).
Either way, the core of the Earth should be molten well past that event. Increasing temperatures (from various factors - both man made global warming but also the sun emits more and more heat as time goes on) are a far more serious concern than the atmosphere blowing away.
"People who think they know everything are very annoying to those of us who do."-Mark Twain
Most scientists think that Mars was once a lot more like Earth in that it had flowing, a thicker atmosphere, and possibly life.
The sun won't go "red dwarf," it will turn into a red giant and will almost certainly swallow up Venus before it runs out of fuel and turns into a white dwarf. Long before any of that happens, the sun will have gotten hot enough to boil away Earth's oceans. The most common figures that I've seen is something like a 500 million to a billion years before the sun boils the oceans and makes Earth uninhabitable and five billion years before it turns into a red giant and swallows up Mercury and Venus. So we do have some time before we need to move.
Does this