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Signs Of Water Found On Distant Planets
nphillips writes "According to this article at CNN, an Italian team has found evidence of water on three planetary systems. The team used a 32-meter radio telescope to search for water maser emissions, telltale microwaves which could indicate water in a planet's atmosphere when it is bathed in the infrared light of its star."
I wonder if they only look for water? Wouldn't there be other elements they could detect using the same methods?
Most extrasolar planets are less than 150 light years away which is nothing in geologic time. Refer to The Extrasolar Planets Encyclopaedia for more information. The finding of the 100th extrasolar planet was reported yesterday.
This is atmospheric water, not surface water that they have, presumably, found. Mars has only a tiny bit of water in its atmosphere, just 210 parts per million. Europa has practially no atmosphere at all, just a tenuous one of oxygen at 1e-11 bar of pressure. If we find a planet with more water in its atmosphere than Mars or Europa, it will be at least the second most watery planet we know of!
$#!^ happens, but why does it always have to happen to me???
Ie; What the hell is a maser? What does it emit? Am I the only one reading CNN that isn't an astrophysisist?
A "maser" is the microwave equivalent of a laser, operating on rotational energy states instead of vibrational states or electron shell jumps. Ammonia is what was used in the first maser built on earth, but other chemicals work too.
Maser action occurs naturally under various conditions. The one I remember reading about was maser emissions from the outer envelopes of (if I recall correctly) red giant stars, as these are cool enough to have molecular matter instead of plasma in the outermost layers.
Detection of a water maser in a distant star system definitely indicates that water is there. Whether it's in the upper atmospheres of planets or just in the outer layers of the host star is another question.
"But it frustrates me that so many scientists always seem to believe that water in a liquid form is a necessity of life."
...
Scientists do not have to believe anything that was not proven yet. Put out a theory that can be tested and maybe then you'll have the right to get frustrated with people who always require some kind of evidence to exist before they start believing in things that they have not seen or proven theoretically.
Water is the best solvent known to our kind that stays liquid between degrees 0C and 100C at ground atmospheric pressure and protected by layer of ozone from various types of radiation from being broken down into oxygen and hydrogen by high energy elements.
There are other types of chemicals that can become solvents: Ammonia, for example melts at negative 77C and boils at negative 33.5C So it is not impossible to use ammonia as a solvent at lower temperatures to do the same things water does at our temperatures. However, notice that with ammonia as a solvent, the actual energy in the system is much lower than in the system at higher temperatures. Thus the chemical reactions will happen much slower if ammonia is used as a solvent at lower temperatures. On the other hand, at higher temperatures some forms of liquid metal can be used as solvents, the problem with those is that at such temperatures things burn. Of-course here comes silicon. Silicon is known to be almost as good at creating long chains as carbon, but not exactly as good. In nature long carbon chains are much more prevalent than long silicon chains, in space we find alcohol molecules - a mix of hydrogen, oxygen and carbon atoms. B.T.W. Carbon is a much more common element in the universe than silicon:
4 1H --> 4He.
3 4He --> 12C.
12C + 4He --> 16O.
12C + 12C --> 24Mg.
etc. making 28Si, 32S,
This is the life of main sequence star, where every next stage is less possible and is much shorter than the previous one and every next stage requires more energy (pressure-temperature) to continue the thermonuclear reactions going. Carbon in these reactions are found much earlier than silicon thus there is more carbon in the universe than there is silicon.
Anyway, my point is that there is no reason to get frustrated with scientists. The science will explain everything to us in due time.
Cheers.
You can't handle the truth.
But it frustrates me that so many scientists always seem to believe that water in a liquid form is a necessity of life. Just because it was required in our form of life doesn't mean that there aren't silicon-based life forms out there, or bacteria that thrive in environments other than H20.
It turns out that water has a number of unusual properties that makes it very friendly to life compared to most other substances.
Among other things, it's a wonderful solvent, and water ice is less dense than liquid water (meaning that a pond freezes _over_, leaving habitable liquid water underneath, instead of freezing solid from the bottom up).
While you can make a strong argument for life being _possible_ in other media, it certainly seems to be most _likely_ to occur in a water-based environment.
Also, finding a world that can support water-based life would be one hell of a PR boost, as it makes the general public consider the possibility of human colonies there (practical or not). An environment habitable to silicate bugs doesn't quite grab the cultural imagination the same way.