What all this makes rather clear is that out gassing from the comet asrecently observed in action is carbon rich, but that the gasses are broken downinto their constituent elements and accelerated through their interaction withthe solar wind. Thus we get the classiclong tail associated with young comets. This as I anticipated must consist of substantial quantities ofelemental carbon. It always amazes methough when the actual picture of a phenomena is pieced together how muchricher it all is.
It is frustrating to not be able yet to travel in exploratory expeditionsto the Oort cloud. I suspect that the gross mass of the Oort cloud has beenseriously underestimated and much is simply unassembled
Question? Does the Oort cloudacquire more interstellar gas than it loses? One assumes we are somewhat in dynamic equilibrium with our place in thegalaxy but we will be passing through dusty regions.
People born today will live to travel in MEV craft travelling at one Gacceleration to explore the Oort cloud. The solar system will be fully explored in person in this century withsuch craft. (read my article on reverseengineering the UFO here or in Viewzone.com)
Research Points To BetterUnderstanding Of Carbon In Comets
by StaffWriters
Researchers have used the presence of long-chain carbon-containing molecules in comets, including some simpleamino acids, as evidence that comets may have brought the seeds of life toEarth.
Using acomet as a far-flung laboratory, a Planetary Science Institute researcher hasshown that the ionization lifetime of carbon is much shorter than what iscurrently used in calculations by comet scientists.
An accurate ionizationlifetime is critical to understanding the amount of carbon released fromcomets, said Jeff Morgenthaler, senior scientist at PSI.
A shorter lifetimesuggests that the carbon content of some comets may be lower than previously estimated. Thiswork could affect current ideas about where comets formed in the early solarsystem and the role they may have played in bringing the seeds of life toEarth.
"Carbon is animportant atom for lots of reasons," Morgenthaler said. "We need toknow how much carbon there is in comets and in what molecules it can be found toanswer some of the questions that have been posed."
Using wide-fieldimages recorded by the Galaxy Evolution Explorer (GALEX) satellite,Morgenthaler produced extremely high-quality radial profiles of atomic carbonemissions from comet C/2004 Q2 (Machholz).
Unlike conditions seenon Earth, a comet's coma, or envelope around its nucleus, is a very simpleatmosphere with no gravity and no magnetic field, and is only affected by thesolar photon and solar wind environment, Morgenthaler said.
"Since otherresearchers have established how fast the carbon moves away from the comet, wecould use the fall-off of the light as a function of distance to measure howlong the carbon lives in the interplanetary medium before it is ionized,"said Morgenthaler, lead author of a recent paper on the topic that appeared inthe Astrophysical Journal.
"We got a chanceto check a lot of calculations at once with our measurement," he said."We found that a carbon atom is ionized after seven to 16 days, dependingon solar activity and solar wind conditions."
This marks the endpoint of the destruction of all of the more complex carbon-bearing moleculesfound in comets.
Researchers have usedthe presence of long-chain carbon-containing molecules in comets, includingsome simple amino acids, as evidence that comets may have brought the seeds oflife to Earth.
"We need to pullback a few more layers of the onion to see if the signatures of the long-chaincarbon-bearing molecules are detectable in these data," Morgenthaler said."We definitely see the signatures of carbon monoxide and methane."
The research foundthat more than just sunlight was affecting the carbon from the comet.
"Something washitting the carbon: the solar wind," he said. "This had beenpredicted earlier, but until now no one had quantitatively put all the piecestogether and done a measurement that confirmed it."
The research wasfunded by a grant to PSI from the GALEX Guest Investigator program.
GALEX's wide field ofview at 1 degree is 10 times larger than the typical ultraviolet telescopesused for similar research, he said. This allows GALEX to capture essentiallyall the emission from the comet, resulting in far more accurate results.
Co-authors of theAstrophysical Journal paper are Walter M. Harris, Department of AppliedSciences, University of California at Davis; Michael R. Combi, Department ofAtmospheric, Oceanic and Space Sciences, The University of Michigan;Paul D. Feldman, Department of Physics and Astronomy, The Johns HopkinsUniversity; Harold A. Weaver, Space Department, Johns Hopkins UniversityApplied Physics Laboratory.
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