Posted on 06/16/2004 2:30:59 PM PDT by ckilmer
Did comets flood Earth’s oceans?
Did comets flood Earth's oceans?
16 June 2004
Did the Earth form with water locked into its rocks, which then gradually leaked out over millions of years? Or did the occasional impacting comet provide the Earth’s oceans? The Ptolemy experiment on Rosetta may just find out…
The Earth needed a supply of water for its oceans, and the comets are large celestial icebergs - frozen reservoirs of water orbiting the Sun. Did the impact of a number of comets, thousands of millions of years ago, provide the Earth with its supply of water? Finding hard scientific evidence is surprisingly difficult.
Artist's impression of Rosetta orbiter and lander
Ptolemy may just provide the information to understand the source of water on Earth. It is a miniature laboratory designed to analyse the precise types of atoms that make up familiar molecules like water.
Atoms can come in slightly different types, known as isotopes. Each isotope behaves almost identically in a chemical sense but has a slightly different weight because of extra neutrons in its nucleii.
Ian Wright is the principal investigator for Ptolemy, an instrument on Rosetta’s Philae lander. By analysing with Ptolemy the mix of isotopes found in Comet 67P/Churyumov-Gerasimenko, he hopes to say whether comet water is similar to that found in Earth’s oceans. Recent results from the ground-based observation of another comet, called LINEAR, suggested that they probably are the same.
If this is true, then scientists have solved another puzzle. However, if the comets are not responsible for Earth’s oceans, then planetary scientists and geophysicists will have to look elsewhere.
For example, the answer could be closer to home, through processes related to vulcanism. Also, meteorites (chunks of asteroids or comets that fall to Earth) have been found to contain water but it is bound to the minerals and in nothing like the quantity found in comets.
However, since the Earth formed from rocks similar to the asteroids, it is feasible that enough water could have been supplied that way.
If comets did not supply Earth’s oceans then it implies something amazing about the comets themselves. If Ptolemy finds that they are made of extremely different isotopes, it means that they may not have formed in our Solar System at all. Instead, they could be interstellar rovers captured by the Sun’s gravity.
Rosetta, Philae and Ptolemy will either solve one scientific mystery, or open another whole set of new ones.
Europe's comet chaser
• - (http://www.esa.int/SPECIALS/Rosetta/index.html)
More about...
• Rosetta factsheet (http://www.esa.int/esaSC/SEMJUZS1VED_index_0.html)
Related articles
• New destination for Rosetta, Europe's comet chaser (http://www.esa.int/SPECIALS/Rosetta/SEMLSFS1VED_0.html)
• Landing on a cosmic iceberg (http://www.esa.int/esaSC/SEM6N12A6BD_exploring_0.html)
• ANIMATION: Life of a comet (http://www.esa.int/SPECIALS/Rosetta/SEM3NV0PGQD_0.html)
• Asteroids: The discovery of asteroids (http://www.esa.int/esaSC/SEMDVF9YFDD_index_0.html)
Related links
• Arianespace (http://www.arianespace.com)
• Astrium Space (http://www.astrium-space.com/)
• DLR (http://www.dlr.de)
I really, really doubt this hypothesis. It would require millions of comets to provide enough water.
If you could grap an ice comet and land it on the moon, you would have the missing ingredient to make lunar colonies possible. There wouldn't an immediate business application since just snagging the comet would cost $ billions and building the colony would be a lot more.
Maybe there were super-Democrats on primordial Earth, and instead of just crying a river, they went the whole hog.
What sort of dipsh*t 'scientist' can only percieve these two possibilities?
that is the most innane thing i ever heard. Must be government funded researchers wasting time and money.
Wasting European time and money -- it's from ESA.
This sounds to me like a case of money-scrabbling for their pet project.
Isn't that how some nazis believed the master race got here?
Seriously.
Silly -- the moon was formed from the recently discovered "cheesy asteroids."
The oceans came from runoff from the rain in Washington State. I thought everyone knew that.
I cast my vote for the water from comets theory.
The moon wouldn't have been able to retain the water, however.
It's Bush's fault.
Ping.
That's true. The moon is much smaller, though, and doesn't have enough gravity to retain an atmosphere. So if we land an icy comet on the moon for the water, we would have to throw a tarp over it right away or it would all eventually just boil off.
I have read that this theory surmises that we are constantly being "hit" with small comets of water all the time. Interesting theory. It would also explain water on Mars.
I believe our solar system once contained a lot more asteroids and comets than i does today.
This comet theory is, imho, just more liberal/left junk-science. It demonstrates once again the degrading effect of the liberal/left mentality on academia and scientific investigation. The classical and much more likely theory is that the earth's water was formed by the ignition of hydrogen and oxygen in the atmosphere. Mix hydrogen and oxygen in a testube and ignite it and you get a reaction in the form of an explosion, of which one of the by-products is water.
"The empirical habit of thought, on which all the scientific achievements of the past were founded, is opposed to the most fundamental principles of Ingsoc (english socialism)." --'1984'
"Science and technology were developing at a prodigius speed, and it seemed natural to assume that they would go on developing. This failed to happen... partly because scientific and technical progress depended on the empirical habit of thought, which could not survive in a strictly regimented society. ...Certain backward areas have advanced, and various devices, always in some way connected with warfare and police espionage, have been developed, but experiment and invention have largely stopped." ---'1984'
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