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Halloween Solar Storm Nearing Heliopause
PipianJ writes "Various sources are reporting that NASA has been tracking the Halloween solar storms of last year as they head towards the end of the solar system and the beginning of interstellar space, the heliopause, in the near future. In related news, scientists now believe that it was solar storms that ripped water from Mars, causing it to be the dry barren wasteland it is today."
Mars has very little atmosphere, and almost no protection from radiation. This renders the surface open to bombardment, and thanks to low gravity and low magnetism, the atmosphere leaks away into space. The article states that the water that might have been on mars 'boiled off' due to solar radiation.
The article states that we have a Magnetosphere, Mars doesn't.
That is our protection. Over 3.5 million years, without that protection, it's POSSIBLE that the water was blown off of Mars.
My mom says I'm cool.
The theory is fairly simple. You have a planet with little or no magnetic field to deflect the solar wind. Add to that a relatively weak gravatational field to keep the gasses stuck to the planet and you have this situation..
Water vapor ends up in the upper atmosphere. High speed solar wind strikes the atmosphere and carries it away. This results in lower atmospheric pressure leading to an increased amount of liquid water turing to vapor and being carried away as well.
As far as where it would go, its generally carried "out" in the direction of the solar wind.
Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
Earth has a stronger gravity to compensate. Also, it would not suprise me in the slightest if the Earth's magnetic field somehow assisted in the matter.
File under 'M' for 'Manic ranting'
go here for cool animations.
My life in the land of the rising sun.
Oddly enough a recent nova discussed this as a sidenote about magnetic pole reversals of the earth. The discussed that eventually the earths magnetic field would disappear as a result of the process, which would last 300 years. During this we would have a constant, global aurora.
They discussed to a good length that the failure of magnetosphere of mars had stripped it of its atmosphere and water.
Since I got rid of cable I have honestly rediscovered why Public broadcasting is great, as I would have never found this degree of depth on discovery channel.
Long-term, I suppose this is correct. However, providing it is possible to create an atmosphere, it should also be possible to maintain one as well. Radiation would always be a problem, atmosphere or no atmosphere. It makes you realize how convenient magnetic fields are at shielding radiation.
;^)
But who knows? Maybe it's easier to terraform Venus, though there's that slow rotation period to worry about. Anyone have any guesses on how to speed up a planet?
--- Journals are boring; Go to my web page instead
My astronomy professor believed that the basic problem was the low mass of Mars. This resulted in a high surface/volume ratio compared to the Earth, causing Mars to cool off more quickly and the interior of the planet solidified, shutting off its magnetic field. Combined with a lower escape velocity, this allowed most of the atmosphere to leak out into space and be stripped away by the solar wind.
Mea navis aericumbens anguillis abundat
One of the theories is that since Mars is smaller than Earth it may have cooled off faster. Since the magnetic field of a planet is generated by the spinning of the core if a planet were to cool sufficiently the core would slow down (the speeds of the core and the crust would begin to match) and thus the magnetic field would weaken.
This theory is supported by the fact that there is little or no tectonic activity currently occurring on Mars, although there certainly has been tectonic activity in the past.
Sapere aude!
Erm, Venus has no magneto sphere either, you know.
That said, since it does sport a huge iron core maybe if we spun the planet the magnetic field would come along too. Though it would be interesting to see what effect would it have on the earth's magneto sphere (magnetic tidal forces?). It would suck if earth's magneto sphere disappeared because of it.
Though maybe we can send a team of crackpots to detonate some nukes in the core. Oh gosh that was a terrible movie. but hey! maybe we can do that for venus!
My life in the land of the rising sun.
Were you disappointed by the movie not working? Two errors were in the link.
This is the working link,
And here's a link to the movie itself.
You are confusing me with someone who cares.
Erm, Venus has no magneto sphere either, you know.
p ersonnel/russell/pap ers/venus_mag/
Serves me for not looking up the specific facts.
Link for explaining Venus's lack of a magnetosphere (it's pretty self-explanatory):
http://www-ssc.igpp.ucla.edu/
The supposition by this article claims that Earth kept its magnetic bubble due to "stirring" of the core (most likely due to tidal forces from not having a tidal-locked rotation period, I would guess).
So, increasing the rotation would be just the key I would think to introducing a magetic field. Of course, someone here also said that a small planet colliding with that planet would be the trick to increasing its rotation. Since the entire planet would be converted to magma as a result of that collision, I think that would be the perfect solution to creating a good magnetoshpere (thanks to the trusty dynamo effect).
--- Journals are boring; Go to my web page instead
The volume of a sphere is: 4/3 Pi r^3
The surface area of a sphere is: 4 Pi r^2
So the volume of a sphere goes up as it's radius (width) to the power of 3, but the area only goes up with the power of 2. So the volume increases much much faster then the area does.
Ex:
^1 | ^2 | ^3
5 | 25 | 125
10 2 times as much | 100 4 times as much | 1000 8 times as much
15 3 times as much | 225 9 times as much | 3375 27 times as much
As you can see from my little chart, to the power of 3 grows way way faster then ^2 does. Power of two grew from 4 times as much as the first entry to 9 times as much, but power of 3 grew from 8 to 27 times as much as the first entry.
-Ariel
This is due to differences in how Mars formed. Irregularities in the field of primordial gas present in the solar system before the formation of planets occurred in such a way that the Earth arose from a hard metallic core rotating quickly, but Mars formed from a less dense and dynamic clump of matter. As a result the Earth has a spinning metallic core that generates a powerful magnetosphere and keeps the planet's mantle heated and molten, but Mars cooled long ago and has little magnetism.
Mars, without a magnetic field to deflect harmful cosmic rays, saw its atmosphere and water irradiated. It is commonly known that molecules bombarded by high energy rays change energy states and often ionize. Earth's thick and magnetically protected atmosphere stayed safe below a thin layer of ozone that absorbs incoming UV radiation , but the inner atmosphere of Mars would become the equivalent of one huge ozone layer, reaching the surface. Ozone is a dangerous chemical capable of reacting with other substances on the surface much like nail polish remover acts on its target.
Soon Mars was reduced to a collection of high energy ionized gases over a rock surface, and an intense greenhouse effect set it. Think about your breathing-while you manually breathe in and out, carefully controlling your respiratory process in order to avoid suffocating, air that has already been processed builds up and creates pressure for release. The oxygen rich air goes down easy, but the used air wants to come out. It's the same for a planet-the remaining gases on Mars heated and energized until they escaped the planet's gravitational pull. Over millions of years this process stripped Mars of all water and organic substances, leaving it the barren wasteland it is today.
To remedy this during a terraforming process, it would be necessary to either constantly produce a fresh supply of oxygen to replace that which is lost, or inject the core with enough metallic matter to reach critical mass and build up the same type of core found within the Earth. Some far-out proposals suggest engineering a collision between Mars and one of its moons, such as Phobos or Deimos, in order to increase mass and introduce energy into the core.
Yes we are still receiving stuff from the voyager craft I remember reading a paper about it rcently in Nature. A link to the abstract is here It may not be as pretty as the pictures we got from the outer planets but I find it amazing that such old technology can still help us do science despite the fact that it is so far away it warps your mind trying to think about it. I wonder how long the voyager craft will stay operational or what kind of computer hardware/software it used. I guess a google search could tell me but I don't have time for that now.
Truely far out, as I believe phobos and deimos much less massive than mars.
if my calculations are right, 59 billion phoboses would equal about one mars.
. and it would take 286 billion deimoses to equal one mars. they're really insignificant moons.
There isn't concensus on where the water have gone, the only thing we know for sure is, there was a lot of water before, and there isn't now.
I work closely with the Mars scientists at Copenhagen University. They designed the magnets on the Mars Rovers. If you ask any one of those for their official oppinion on where the water went, most likely they will just say "erhhh?!", because really nobody has clue. Some calculations conclude that even with the weak magnetic field, the boiling off of water would not go fast enough for all the water to evaporate into space.
Most of the water may still be there, but hidden underground as permafrost.
Hell, yeah! I believe that Voyager is doing its' most important work RIGHT NOW. After the Neptune flyby, the planetary science teams packed up and left, and a new crew of solar and interstellar scientists took over the lab, to remain there until Voyager's batteries run out, in the year 2020.
As we speak, Voyager 1 is more than twice the distance from the Sun to Neptune, maybe even three times as much. Voyager 2 is lagging behind a bit. Whatever the exact distance, the Voyager Twins are alive, well, and broadcasting from the very edge of the Solar System.
First, a bit of definition: a Solar or Interstellar Wind is not really wind, but particles travelling through space at great speeds. Our own Solar Winds zoom away from the Sun at about a million mph; it is poetically referred to as a Supersonic wind.
Solar winds race outward like an expanding bubble. Interstellar winds bombard us from all directions. There is a high-turbulence zone where these winds clash head-on; very little penetrates either in or out. This zone is called the Heliopause, where Solar Winds slow down from Supersonic to a hundred thousand mph. During a Solar Maximum, when our winds push the hardest, the Heliopause expands in area. Conversely, during a Solar Minimum, the Heliopause deflates.
On August 1, 2002, Voyager 1 measured Solar Winds at a hundred thousand mph! However, eight months later, the winds went back up to Supersonic, and have remained that way. Voyager 2, lagging behind, has detected no change at any point in time.
What does this mean? Well, Voyager 1 left the direct influence of the Sun, then some months later the bubble expanded, and Voyager 1 is back under the influence.
This has been a source of controversy, since way too few interstellar particles were detected, according to what current theorists expected. But then again, we ARE in uncharted territory, aren't we?
Lil' Thindime, lilting a lacrimose lament, krashes the kwaint konfines of Kokonino Kounty
There's more too it than that...
The primary difference is in the masses. The Earth is much more massive, so it has more gravity. That allows it to keep more gasses in its atmosphere. O2 for instance would easily get escape velocity on mars and leak out. So mars's atmosphere leaked out due to low gravity, this is the first step in the problem.
Secondly, the earth (by virtue of being heavier) has a lower surface area to volume ratio. So it loses heat slower with time. That is why our core is still molten. Mars probably had a molten core at one time, but it cooled off, and that was the end.
In addition, because the earth was heavier it got more heat from collisions (due to greater gravity) to begin with. So we not only keep heat more efficiently, we also started with more heat per unit of volume.
Also, much of the earth's heat is believed to be produced by the decay of radioactive elements, once again the lower surface are to volume (mass actually) ratio helps to keep that heat in, which keeps our core molten.
The liquid core that the earth still has (Venus has one too) produces the magnetic field. Our gravity is greater so most of the atmosphere can't escape, and thus we're relatively radiation hardened. In addition, the oxygen in the atmosphere (formed by primitive life) efficiently captures hydrogen (to form water) and thus keeps the hydrogen from leaking out. The solar winds deliver additional hydrogen (nicely funnelled into the poles) that replaces anything that was lost.
There really is a lot to it, but the basic factors are...
1) The earth is larger, so the core is still hot and we keep our atmosphere. Hot core generates magnetic shielding.
2) The earth has lots of oxygen (due to life), which traps hydrogen and keeps the surface cool because it is not a greenhouse gas. Oxygen also produces ozone that adds extra shielding. Mars is too light to keep oxygen even if we did generate it to begin with.
Slight misstatement. If you assume that the density is about the same (fairly reasonable), then the mass is proportional to the volume. A heavier planet has a larger volume (once again, since earth and mars are both rocky planets), and thus a lower surface area to volume ratio.
So the surface area to volume ratio is...
S/V = 3/r
but (if the densities are the same) (4/3)[pi]r^3 = M
and thus r = ((3/4[pi])M)^1/3
And thus S/V = 1 / (M/4[pi])^1/3
and this decreases with increasing mass, though not that quickly.
In space the matter is spread out much more than here on earth, which means the speed of sound through the various gases (mostly hydrogen, helium nuclei, electrons, and protons), is different. Since the gases are all spread out, the mean free paths between gas particles is pretty big. That means that your speed of sound is going to be greater.
But there is another catch!
Because the gases in space have a sigificant amount of charged particles, there is also a coupling effect between the electromagnetic field and the speed of sound. You essentially have TWO speeds of sound: one from the gas molecules bumping into each other; and one from the plasmadynamic interactions between the gas particles causing magnetosonic waves which have their own wave speed. The magnetosonic waves can only happen in a gas that is at least partially ionized.
The heliopause is a prime example of a magnetosonic shock. It's theorized to be pretty much a standing shock wave (standing still from our point of view). The heliopause should also have a sonic shock from the clashing of different materials at different speeds (two gas flows coming at each other). One gas will force the other gas to slow down; which forces the slowed-down-gas to form a shock.
In space, the speed of sound is REALLY big. 100 km/s is not an uncommon speed of sound. The magnetosonic waves should travel at speeds between the speed of sound and the speed of light. Magnetosonic wave speeds vary on how many ions exist in the gas, and on how much electromagnetic energy is transported through the gas.
Don't blame the scientists for the difficulty that you are having with these concepts. Instead read more of their papers and source material and perhaps you will see what they are talking about.
The universe is not a place with evenly distributed material and perfectly omnidirectional forces. There are flaws in any gas cloud and this leads to eddies and whorls. Some of these are larger than others and thus trap more material. The larger ones coalesce into larger astronomical objects and the smaller ones tend to form smaller objects.
This form of aggregation occurs on all scales. Microscopic particles of dust can accrete into large clumps, large bodies can become larger or smaller depending on their environment. You can see this accretion in the rings of Saturn where it is likely that the bands are forming from interactions between the material that the rings is composed of. There is also good evidence that it is occuring in nebula
When the loose material is blown away from an astronomical object the amount left behind will depend on a lot of factors such as the amount and type of atoms that were in the gas cloud, the size of the gas cloud, the motion of the gas cloud, the size of the newly formed sun, etc.
Sapere aude!