Tarlike macro-molecules detected in 'stardust' (Forwarded)
Robert Clark
"Kevin Keogh" <kevin...@earthlink.net> wrote:
>
> So the first evidence of interstellar dust shows that it consists of
large,
> complex organic molecules. Does this surprise anyone? Any comments on
how or
> where these large organic molecules were formed?
>
> Kevin Keogh
>
>
It would be interesting to determine if this "tarlike" material is
actual tar since on Earth real tar is due to the combustion or decay of
living material. I wrote about this in a post on some scientists whose
research they say is supportive of the idea that life is ubiquitous in
the universe:
********************************************************
Forum: sci.astro
Subject: Re: Exobiology and the Fermi paradox.
Date: 12/28/1999
Author: Robert Clark <rgc...@my-deja.com>
In article <83rnd3$dmr$1...@nnrp1.deja.com>,
Robert Clark <rgc...@my-deja.com> wrote:
>
>
> A nice article describing the prevalence of organic compounds
> throughout the universe and therefore the likelyhood of life is on the
> Popular Mechanics site:
>
> Alien World
> Starting discoveries by NASA scientist suggest the universe may be
> teeming with exotic life-forms.
> Popular Mechanics, July 1999
> http://popularmechanics.com/popmech/sci/9907STSPAM.html
> [Nice illustration by Alan Gutierrez here.]
>
> Nevertheless, physicist Frank Tipler takes the view that the
solution
> to the Fermi paradox is simply that there is no other intelligent life
> other than ours:
>
> Is there anybody out there?
> New Scientist, 23 November 1996
> http://www.newscientist.com/nsplus/insight/astrobiology/isthere.html
>
> --
>
The argument presented by the researchers in the first article for
life in the universe is strengthened by several factors. Firstly, it is
known that comets contain large amounts of organic material. This is
known for example by the observations of the Giotto spacecraft of
Halley's comet and from ground spectroscopic observations. An
intriguing observation of the Giotto mission was of "tar-like" material
in the nucleus of the comet. Actual tar on Earth is due to the
combustion or decay of living matter. It would be interesting to find
out then if this tar observed really is of the same composition as that
on Earth.
Also, carbonaceous meteorites contain large amounts of organic matter
and these are generally agreed to stem from spent comets. It has been
known for sometime that they even contain amino acids. But this was
taken by many to be terrestrial contamination since some show the left-
right amino acid asymmetry only seen in life. However, recent research
shows this chirality in amino acids of meteorites that don't occur in
Earth life, showing the amino acids are indigenous to the meteorite.
And geologist Robert Folk argues that the majority of carbon in
carbonaceous meteorites is in fact due to nanobacteria.
Finally, the leading theory of the origin on the organic material in
comets is that they stem from the interstellar clouds that have been
observed to contain organic matter.
Then if it is determined that comets in our system contain active or
fossilized life then since the organic material in comets comes from
interstellar clouds that would strongly suggest that such life exists
in other systems as well, either in the clouds themselves or in comets
that travel to other systems. Note therefore that there are several
spacecraft planned or en route to rendevous with comets to determine
their composition, notably the Stardust mission launched this year.
The New York Center for Studies on the Origin of Life has several audio
interviews online that concern astrobiology:
WAMC's Environment Show Origins of Life Segments,
www.rpi.edu/~straca/NSCORT/WAMC_interviews.html
[RealAudio required]
Segment 13 - Dr. George Flynn, Physics Department at SUNY Plattsburgh
and Dr. Wayne Roberge, Professor of Physics at Rensselaer Polytechnic
Institute,
www.wamc.org/audio/envshow/org13.ram
[Dr. Roberge suggests that the Miller-Urey experiment for the creation
of amino acids actually took place in space; Dr. Flynn suggests that
the rain of organic matter in space dust contributed to the origin of
life on Earth.]
Segment 15 - Dr. William Irvine
Five College Radio Astronomy Observatory, University of Massachusetts,
www.wamc.org/audio/envshow/org15.ram
[suggests that the organic matter in comets stems from interstellar
clouds and 1/3 to 1/2 of the solid matter in Halley's comet was
organic.]
Carbon in the Universe,
Science, Vol. 282, No. 5397, 18 Dec 1998, pp. 2204 - 2210,
www.sciencemag.org/cgi/content/full/282/5397/2204
[organics in interstellar clouds and in comets]
Carbons from Heaven
Building the Building Blocks of Life
204.202.137.114/sections/science/DailyNews/spacecarbon990218.html
COMETS: THE DELIVERY SYSTEM
www.panspermia.com/comets.htm
[from Brig Klyce's Panspermia site, discusses the theory that comets
delivered the first life to Earth.]
CAN THE THEORY BE TESTED?
www.panspermia.com/cantest.htm
[from Brig Klyce, discusses how to verify the cometary origin of Earth
life.]
AMINO ACID ASYMMETRY IN THE MURCHISON METEORITE!
www.panspermia.com/chiral.htm
[from Brig Klyce, discusses the chirality of the amino acids in the
Murchison meteorite.]
AN ATMOSPHERIC TEST OF COMETARY PANSPERMIA,
www.panspermia.org/balloon2.htm
[astronomers Holye and Wickramasinghe discuss using high-altitude
balloons to search for bacteria in the dust from comets entering the
atmosphere.]
The Leonid Sample Return Mission
science.nasa.gov/newhome/headlines/ast16nov98_3.htm
[balloon search for organics (and microbes?) in the Leonids]
Giotto's legacy
astro.geoman.net/us/dossiers/9/rosetta_5.html
What is a comet?
earthsky.worldofscience.com/Features/Articles/comet_hale-
bopp5.html
PHYSICAL STUDY OF COMETS, MINOR PLANETS AND METEORITES
www.ss.astro.umd.edu/IAU/comm15/trirep97/Report97.html
[extensive review of the composition of comets, including the results
of Giotto.]
Comets & Asteriods: Clues to the Early Solar System
ethel.as.arizona.edu/~connie/ast100f97/lecture21.html
[illustrated lecture on the composition of comets.]
Nanobacteria: surely not figments, but what under heaven are they?
naturalscience.com/ns/articles/01-03/ns_folk.html
[Folk presents his argument for the biological nature of nanobacteria
and his view that the organic material in meteorites is due to them.]
Stardust Blasts Off
Comet Chaser Will Gather Cosmic Dust
abcnews.go.com/sections/science/DailyNews/stardust990203.html
**************************************************************
Other links discussing this possibility appear in:
Forum: sci.astro
Subject: Re: Exobiology and the Fermi paradox.
Date: 01/05/2000
Author: Robert Clark <rgc...@my-deja.com>
http://x33.deja.com/getdoc.xp?AN=568674425
You might also find it interesting to read:
Forum: alt.sci.planetary
Subject: Exobiology. (1.) Nanobacteria (was Re: Gravitons and Black
Holes)
Date: 11/16/1999
Author: Robert Clark <rgc...@my-deja.com>
http://x44.deja.com/getdoc.xp?AN=549036591
--
________________________________________________
"In order for a scientific revolution to occur,
most scientists have to be wrong"
-- Bob Clark
________________________________________________
Sent via Deja.com http://www.deja.com/
Before you buy.
Joseph Lazio
RC> In article
RC> <cniO4.4038$g4.1...@newsread2.prod.itd.earthlink.net>, "Kevin
RC> Keogh" <kevin...@earthlink.net> wrote:
>> So the first evidence of interstellar dust shows that it consists
>> of large,
>> complex organic molecules. Does this surprise anyone? Any comments
>> on how or where these large organic molecules were formed?
RC> It would be interesting to determine if this "tarlike" material
RC> is actual tar since on Earth real tar is due to the combustion or
RC> decay of living material. [...]
I don't think it is all that surprising. First, remember that
"organic" is a generic term meaning the substance contains carbon.
Carbon is, relatively, an abundant element.
The dust grains themselves probably formed initially in the outflow
from a cool supergiant. As the material moved away from the star, it
cooled and could condense into small grains. In interstellar space
the dust grains are exposed both to high-energy radiation (UV and
X-ray) and high-energy particles. Both of those carry enough energy
to break bonds and allow chemical reactions to occur. Indeed the
surfaces of a number of moons of the outer planets are covered in a
"reddish" substance which is thought to be an organic "goo" formed in
much the same manner.
--
Lt. Lazio, HTML police | e-mail: jla...@patriot.net
No means no, stop rape. | http://patriot.net/%7Ejlazio/
sci.astro FAQ at http://sciastro.astronomy.net/sci.astro.html
Kevin Keogh
Joseph Lazio <jla...@adams.patriot.net> wrote in message
news:ll4s8ku...@adams.patriot.net...
> >>>>> "RC" == Robert Clark <rgc...@my-deja.com> writes:
>
> RC> In article
> RC> <cniO4.4038$g4.1...@newsread2.prod.itd.earthlink.net>, "Kevin
> >> So the first evidence of interstellar dust shows that it consists
> >> of large,
> >> complex organic molecules. Does this surprise anyone? Any comments
> >> on how or where these large organic molecules were formed?
>
> RC> is actual tar since on Earth real tar is due to the combustion or
> RC> decay of living material. [...]
>
> I don't think it is all that surprising. First, remember that
> "organic" is a generic term meaning the substance contains carbon.
> Carbon is, relatively, an abundant element.
>
> The dust grains themselves probably formed initially in the outflow
> from a cool supergiant. As the material moved away from the star, it
> cooled and could condense into small grains. In interstellar space
> the dust grains are exposed both to high-energy radiation (UV and
> X-ray) and high-energy particles. Both of those carry enough energy
> to break bonds and allow chemical reactions to occur. Indeed the
> surfaces of a number of moons of the outer planets are covered in a
> "reddish" substance which is thought to be an organic "goo" formed in
> much the same manner.
>
Pardon me if I find this somewhat amusing. Suppose I said that DNA and RNA
originated in interstellar space? Would you find that surprising? But
10,000+ molecular CHON (organic rich) molecules are a piece of cake? Do you
know of any references to experiments in which CHON molecules of anywhere
near this size were synthesized under any likely interstellar (or any
extraplanetary) conditions?
Now, I personally am not surprised. An interstellar origin of these
molecules may not be too difficult to cook up. However, when matching
interstellar dust to known molecular spectra, I don't think many scientists
have been concentrating on polymeric heterocyclic aromates. If you know of
any references to interstellar dust spectra models incorporating large
concentrations of 2000+ molecular weight molecules, I would be very
interested. Besides those of Hoyle and Wickramasinghe, that is.
Kevin Keogh
Joseph Lazio
KK> Joseph Lazio <jla...@adams.patriot.net> wrote in message
news> ll4s8ku...@adams.patriot.net...
>> >>>>> "RC" == Robert Clark <rgc...@my-deja.com> writes:
RC> It would be interesting to determine if this "tarlike" material is
RC> actual tar since on Earth real tar is due to the combustion or
RC> decay of living material. [...]
>> I don't think it is all that surprising. First, remember that
>> "organic" is a generic term meaning the substance contains carbon.
>> Carbon is, relatively, an abundant element.
>>
>> The dust grains themselves probably formed initially in the outflow
>> from a cool supergiant. As the material moved away from the star,
>> it cooled and could condense into small grains. In interstellar
>> space the dust grains are exposed both to high-energy radiation (UV
>> and X-ray) and high-energy particles. Both of those carry enough
>> energy to break bonds and allow chemical reactions to occur.
>> Indeed the surfaces of a number of moons of the outer planets are
>> covered in a "reddish" substance which is thought to be an organic
>> "goo" formed in much the same manner.
KK> Pardon me if I find this somewhat amusing. Suppose I said that DNA
KK> and RNA originated in interstellar space? Would you find that
KK> surprising?
Probably, but Nature has a way of being pleasantly surprising.
KK> But 10,000+ molecular CHON (organic rich) molecules are a piece of
KK> cake? Do you know of any references to experiments in which CHON
KK> molecules of anywhere near this size were synthesized under any
KK> likely interstellar (or any extraplanetary) conditions?
From where does the "10,000+" figure come?
KK> Now, I personally am not surprised. An interstellar origin of
KK> these molecules may not be too difficult to cook up. However, when
KK> matching interstellar dust to known molecular spectra, I don't
KK> think many scientists have been concentrating on polymeric
KK> heterocyclic aromates. If you know of any references to
KK> interstellar dust spectra models incorporating large
KK> concentrations of 2000+ molecular weight molecules, I would be
KK> very interested. Besides those of Hoyle and Wickramasinghe, that
KK> is.
Again, I don't know where the "2,000+" figure originates, but if
"polymeric heterocyclic aromates" are the same thing as polycyclic
aromatic hydrocarbons, then there is a rich literature on them. Using
the ADS Abstract Service I found over 200 papers on PAHs, including a
recent one involving both a laboratory and spacecraft experiment:
<URL:http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?bibcode=2000ApJ...531L..71G>.
Kevin Keogh
Quoting from the article above: "At an impact speed of about 30
kilometers/second (18 miles/second) these interstellar dust particles are
vaporized immediately and broken up into molecular fragments. ... 'It is the
size of these molecular fragments with nuclear masses of up to 2000 (water
e.g. has 18 such units) which surprised us as much as the seemingly absence
of any mineral constituents', explains Dr. Kissel."
The 10,000+ figure is just an arbitrary one for complete molecules whose
molecular fragments are 2,000+. I suppose these molecules could have broken
up 2000 in one fragment and 1 in another, but, from the description given,
I'm guessing the naturally occurring, non-impacted molecular weights are far
greater than 2000.
> KK> Now, I personally am not surprised. An interstellar origin of
> KK> these molecules may not be too difficult to cook up. However, when
> KK> matching interstellar dust to known molecular spectra, I don't
> KK> think many scientists have been concentrating on polymeric
> KK> heterocyclic aromates. If you know of any references to
> KK> interstellar dust spectra models incorporating large
> KK> concentrations of 2000+ molecular weight molecules, I would be
> KK> very interested. Besides those of Hoyle and Wickramasinghe, that
> KK> is.
>
> Again, I don't know where the "2,000+" figure originates, but if
> "polymeric heterocyclic aromates" are the same thing as polycyclic
> aromatic hydrocarbons, then there is a rich literature on them. Using
> the ADS Abstract Service I found over 200 papers on PAHs, including a
> recent one involving both a laboratory and spacecraft experiment:
>
<URL:http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?bibcode=2000ApJ...531L
..71G>.
>
> --
They are related, but they aren't the same thing. Which PAH's have 10%
nitrogen and oxygen? Which have 2000+ molecular weights? While I realize
that PAH's are related to tar-like compounds on a "continuum" of polycyclic
aromates, PAH's are flat and far simpler structures in general. It has long
been known that the spectra of interstellar dust resembles the spectra of
auto soot. However, simple PAH's and not complex polymeric heterocyclic
aromates have been traditionally viewed as the most likely candidates for
the diffuse interstellar bands. I'm guessing that interstellar dust is
closer to actual auto soot than has been previously supposed. Please see:
http://www-space.arc.nasa.gov/~astrochm/PAHs.html
For more information on common PAHs and a comparison of the Orion Bar to the
spectra of auto soot.
The next question is where all this "cosmic auto soot" came from.
Kevin Keogh
Joseph Lazio
KK> Quoting from the article above: "At an impact speed of about 30
KK> kilometers/second (18 miles/second) these interstellar dust
KK> particles are vaporized immediately and broken up into molecular
KK> fragments. ... 'It is the size of these molecular fragments with
KK> nuclear masses of up to 2000 (water e.g. has 18 such units) which
KK> surprised us as much as the seemingly absence of any mineral
KK> constituents', explains Dr. Kissel."
KK> The 10,000+ figure is just an arbitrary one for complete molecules
KK> whose molecular fragments are 2,000+. I suppose these molecules
KK> could have broken up 2000 in one fragment and 1 in another, but,
KK> from the description given, I'm guessing the naturally occurring,
KK> non-impacted molecular weights are far greater than 2000.
O.k., let's take the average atom in these compounds to have a nuclear
mass of 10. (Hydrogen has a nuclear mass of 1, carbon 12, nitrogen
14, and oxygen 16, so 10 may even be an underestimate.) Then these
compounds consisted of something like 200 atoms, and their parents may
have had up to 1000 atoms (using your 10,000+ nuclear mass figure).
A quick search of the ADS Abstract Service does show people discussing
interstellar (organic) dust particles containing this number of
atoms.
> KK> Now, I personally am not surprised. An interstellar origin of
> KK> these molecules may not be too difficult to cook up. However, when
> KK> matching interstellar dust to known molecular spectra, I don't
> KK> think many scientists have been concentrating on polymeric
> KK> heterocyclic aromates. If you know of any references to
> KK> interstellar dust spectra models incorporating large
> KK> concentrations of 2000+ molecular weight molecules, I would be
> KK> very interested. Besides those of Hoyle and Wickramasinghe, that
> KK> is.
>
> Again, I don't know where the "2,000+" figure originates, but if
> "polymeric heterocyclic aromates" are the same thing as polycyclic
> aromatic hydrocarbons, then there is a rich literature on them. Using
> the ADS Abstract Service I found over 200 papers on PAHs, including a
> recent one involving both a laboratory and spacecraft experiment:
> <URL:
> http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?bibcode=2000ApJ...531L..71G>.
KK> They are related, but they aren't the same thing. Which PAH's have
KK> 10% nitrogen and oxygen? Which have 2000+ molecular weights? While
KK> I realize that PAH's are related to tar-like compounds on a
KK> "continuum" of polycyclic aromates, PAH's are flat and far simpler
KK> structures in general. It has long been known that the spectra of
KK> interstellar dust resembles the spectra of auto soot. However,
KK> simple PAH's and not complex polymeric heterocyclic aromates have
KK> been traditionally viewed as the most likely candidates for the
KK> diffuse interstellar bands. I'm guessing that interstellar dust is
KK> closer to actual auto soot than has been previously
KK> supposed. Please see:
KK> http://www-space.arc.nasa.gov/~astrochm/PAHs.html
A quick search of ADS reveals no papers on PHAs. So this means that
either nobody's thought of a way to produce them in interstellar space
or nobody's thought to think of a way. I don't know which it is.
However, people are thinking about producing large molecules (100+
atoms) in interstellar space. I'm not a chemist, but if one can
produce large PAHs, why not large molecules having O and N in them,
too? They are, cosmically, relatively abundant elements.
KK> The next question is where all this "cosmic auto soot" came from.
Quoting from the same Web site you cite, "The high temperatures
present lead to the same kinds of molecules that we see in auto
engines." Between the outer envelopes of giant stars and high-energy
particle impacts on dust grains, I think there would be plenty of
activation energy about to power chemical reactions.
Kevin Keogh
Joseph Lazio <jla...@patriot.net> wrote in message
news:llzoqb5...@adams.patriot.net...
> The following message is a courtesy copy of an article
> that has been posted to
sci.astro,sci.astro.seti,rec.arts.sf.science,sci.bio.misc as well.
Certainly the particles discussed are this big. However, the molecules
discussed are not. The particles were thought be many simpler molecules
"stuck together." If you know of any references discussing 2000+ molecular
weight molecules, I would love to read them.
Well, one problem would be the density of material likely to be present.
Also, what percursor chemicals are used in the outer envelopes of giant
stars to forge these complex molecules? We know that to get tar on Earth we
destructively distill complex organic matter--like petroleum. Is there a
bunch of petroleum in these red giant envelopes? I'm sure this idea would
intrigue Thomas Gold, but I doubt that much funding has ever gone toward
examining such possibilities. I don't purport to know the most likely
mechanisms, but high energy collisions in 3 degree interstellar space don't
seem like a very likely way to make complex organic molecules at first
glance. We'll soon see how astrochemists specializing in interstellar dust
interpret these new findings. I don't know about you, but these initial
results have made me even more excited about the prospect of a successful
STARDUST sample return.
Kevin Keogh
Tommy the Terrorist
about polymerized HCN as a basis for life (pretty convincingly).
Basically,
(lots of H) + C, N, O -> CH4 NH3 H20
CH4 + NH3 -> HCN (+3H2)
3HCN -> [ C[=NH]-CH[-C#N]-NH- ] n polymer
(Also, 5HCN -> adenine, somehow...)
The polymer, +H20, hydrolyzes to emit ammonia, and the reactive -C#N
group allows attachment of side chains, to form
[ C[=O]-CH[-R]-NH- ] n polymer
a.k.a. protein
Anyway, the HCN is supposed to be present all over the place in space,
and to form this gunk everywhere, with nifty orange-to-black colors of
various objects actually produced by it. Cool stuff.
douglas dwyer
deja.com> writes
>It would be interesting to determine if this "tarlike" material is
>actual tar since on Earth real tar is due to the combustion or decay of
>living material. I wrote about this in a post on some scientists whose
>research they say is supportive of the idea that life is ubiquitous in
>the universe:
orthodox thought.
I first heard of his name at school in the 50s associated with "Hoyle's
oil" his hypothesis that some or all crude oil condensed from space
with the orig earth mass.
--
douglas dwyer