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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 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;
go here for cool animations.
My life in the land of the rising sun.
..if the solar storms blew away water from mars upper atmosphere during a long period of time, which led to the drying of mars oceans, the same (but maybe in a lesser extent) should have happend to earth.
..and we are next) :(
Because of earths higher gravity, denser atmosphere and our magnetic field this effect might not at all have been that big, but over the billions of years it has probably made a noticeable decrease in earths oceans too?
If we take a look at Venus, a planet we believe had as much water as earth in the past, we find that it has no water either - and no magnetic field but it has about the same gravity as earth and a denser atmosphere => it is quite likely that a magnetic field is much more important for a planet to keep its water, than its atmosphere and/or gravity.
However, as I understand, during the period (several hundreds of years or more?) which the earths magnetic field changes polarity, which happends regularly, we have no magnetic "shield" and together with my statement that denser atmosphere and higher gravity than mars does not matter that much, earth should during this time also have lost some water in the same way as Mars/Venus?
So what am I shooting at here? Well I think it is an interesting question wether we (planet earth) had more water 5 billion years ago, or if it is largely unchanged? Maybe earth was totally covered in water? Maybe we will only have half as much, or no, water in 5 billion years? Or is earth in fact increasing its water-mass by sucking up comets? Are there any such data/measurements?
Maybe if we have such measurements from periods during which we had no magnetic field - we might be able to calculate the effects of solarwinds and thereby maybe evaluate this new Mars-theory plus maybe calculate wether earth might suffer the same destiny as Venus and Mars.
(I think it is quite sad that we are surrounded by all these planets that once was easily terraformable but now they are all "dead".
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
Not necessarily true. Yes, eventually Mars will lose most of its terraformed atmosphere and it will return to the state that it is currently in but that could take millions of years. We can certainly generate a ton more atmosphere than Mars loses and we can do so for a good, long time.
Not only that but if we were really innovative we would redirect a few comets or similar objects into a close orbit around Mars, releasing them onto the planet in a planned manner and further bulking up the atmosphere. This may be a bit beyond our current technology but we should be able to do it fairly soon.
By the time we are ready to terraform Mars we will almost definitely be able to do so.
Sapere aude!
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.
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
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.
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