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(meteorobs) Excerpts from "CCNet DIGEST, 16 July 1999"


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From: Benny J Peiser <b.j.peiser@livjm.acdot uk>
To: cambridge-conference@livjm.acdot uk
Subject: CCNet DIGEST, 16 July 1999
Date: Fri, 16 Jul 1999 13:30:43 -0400 (EDT)

CCNet DIGEST, 16 July 1999
==========================

[...]

(3) TUNGUSKA99 PRESS RELEASE 16 JULY 1999 =3D=3D=3D
    Luigi Foschini <L.Foschini@isao.bo.cnrdot it>=20

[...]

(7) POSSIBLE PLAYER IN ORIGINS OF LIFE?
    Andrew Yee <ayee@nova.astro.utorontodot ca>

(8) AMINO ACID ENANTIOMER AXCESSES IN METEORITES
    J.R. Cronin and S. Pizzarello, ARIZONA STATE UNIV

==========================

(3) TUNGUSKA99 PRESS RELEASE 16 JULY 1999 =3D=3D=3D

>From Luigi Foschini <L.Foschini@isao.bo.cnrdot it>=20

The expedition has left Bologna on July 14, 1999 at 9 o'clock=20
(local time) to reach the Forli' airport by bus. The Iljuschin=20
Il-20 was loaded and land off at 12:00 (local time). Destination:=20
Moscow. Please find attached a photo of the departure from Forli'=20
airport. More photos are available at the web site:=20
http://www-th.bo.infndot it/tunguska/
=20
In Moscow, the expedition has overcome the main difficulty of the=20
journey: the Russian Customs. All the equipement and the=20
instruments were unloaded and inspected. The check takes about 4=20
hours and half. The Russian Customs sequestrates three=20
walkie-talkie only. Prof. Longo tried to explain that, in Italy,=20
even children use walkie-talkie and they are not dangerous. But he=20
does not succeeded in getting back the three walkie-talkie.=20
=20
Apart from this little problem, the expedition goes on. They=20
reached Krasnoyarsk on July 15 and they loaded the helicopter=20
Mi-26, that will be used to reach the Ceko lake. We have also=20
carried out a communication test by satellite telephone: it is all=20
right. They will leave Krasnoyarsk on July 16, at 10:00 local=20
time.=20
=20
More informations are available at the Tunguska Home Page, that=20
will be continuously updated also during the expedition, with=20
reports from the field:
=20
http://www-th.bo.infndot it/tunguska/
=20
For the Tunguska99 Press Office:
Luigi Foschini (mailto:L.Foschini@isao.bo.cnrdot it)

==========================

(7) POSSIBLE PLAYER IN ORIGINS OF LIFE?

>From Andrew Yee <ayee@nova.astro.utorontodot ca>

University of Hawai'i
University Relations
Media & Publications
Honolulu, HI 96822
Telephone (808) 956-8856
Facsimile (808) 956-3441
E-Mail: ur@hawaiidot edu

Contact:
Cheryl Ernst
University of Hawai'i
808-956-5941, ernst@hawaiidot edu

Luann Becker
UH Manoa, c/o Scripps Institution of Oceanography
619-534-2995

For other Work by Luann Becker, see http://govt.us.oracle.com/~mars/

Louis Allamandola
NASA Ames Research Center Space Science Division
650-604-6890

Theodore Bunch
NASA Ames Research Center Space Science Division
520-717-1916

For Immediate Release: July 14, 1999

POSSIBLE PLAYER IN ORIGINS OF LIFE?

University of Hawai'i Researcher Finds a New Form of Pure Carbon in a
Mexican Meteorite

A University of Hawai'i researcher and her colleagues from the NASA=20
Space Science Division have confirmed that a new form of carbon=20
previously made in the laboratory also exists in nature. The finding=20
indicates that the pure carbon molecules known as fullerenes could have =

been a factor in the early history of Earth and might even have played=20
a role in the origin of life.

University of Hawai'i at Manoa organic geochemist Luann Becker and NASA =

colleagues Theodore E. Bunch and Louis J. Allamandola discovered the
presence of fullerene carbon molecules in the 4.6-billion-year-old =
Allende
meteorite, which has been of interest to scientists since it landed in=20
Mexico three decades ago.

The scientists' report will appear in the July 15 issue of the British=20
journal Nature. Becker shared their findings with fellow scientists=20
during the triennial meeting of the International Society on the=20
Origins of Life this week in San Diego, Calif.

"It's not every day that you discover a new carbon molecule in nature;=20
that's what makes this interesting," Becker says. "If it played a role=20
in how the earth evolved, that would be important."

Fullerenes are soccer-ball shaped molecules (hence their name, which=20
honors geodesic-dome designer Buckminster Fuller) of 60 or more carbon=20
atoms. Their discovery in 1985 as only the third form of pure carbon=20
(along with diamonds and graphite) earned U.S. scientists Robert F.=20
Curl Jr. and Richard E. Smalley and British researcher Harold Kroto the =

1996 Nobel Prize in Chemistry. The trio accidentally synthesized these=20
three-dimensional forms of carbon molecules in the laboratory while=20
trying to simulate the high-temperature, high-pressure conditions in=20
which stars form.

Scientists hypothesized that fullerenes also exist naturally in the=20
universe. Becker, who earlier discovered the presence of fullerenes in=20
deposits at the site of the Sudbury impact crater in Ontario, Canada,=20
and her colleagues were able to document naturally occurring fullerenes =

by exploiting a unique property characteristic of organic molecules.=20
Unlike their pure-carbon cousins, which maintain a solid state,=20
fullerenes can be extracted in an organic solvent.

Becker crushed a piece of the Allende meteorite, demineralized the=20
sample with acids, and used the organic solvent to extract fullerenes=20
from the residue. The scientists found not only the C60 and C70=20
molecules believed to be most prevalent, but also significant=20
quantities of C100 to C400 molecules. This is the first discovery of=20
higher fullerenes in a natural sample.

Because the multiple atoms in the molecule form a hollow, closed cage=20
that can trap gasses inside, they may have delivered from their stellar =

birthplace both the carbon that is an essential element to life and the =

volatiles that contributed to the planetary atmospheres needed for the=20
origin of life. At the very least, the molecules and their contents=20
will tell scientists more about the early solar nebula or presolar dust =

existing when meteorites like Allende were formed.

The research is supported by a grant from the NASA Cosmochemistry =
Program.

==========================

(8) AMINO ACID ENANTIOMER AXCESSES IN METEORITES

J.R. Cronin*) and S. Pizzarello: Amino acid enantiomer excesses in=20
meteorites: Origin and significance. ADVANCES IN SPACE RESEARCH, 1999,=20
Vol.23, No.2, pp.293-299

*) ARIZONA STATE UNIV,DEPT CHEM & BIOCHEM,TEMPE,AZ,85287

The presence of small L-excesses in both of the two enantiomeric pairs=20
of 2-amino-2,3-dimethylpentanoic acid, in 2-amino-2-methylbutanoic acid =

(Isovaline), and in 2-amino-2-methylpentanoic acid from the Murchison=20
meteorite has also been observed in these amino acids as extracted from =

the Murray meteorite. As in Murchison, the alpha-hydrogen analogues of=20
the latter amino acids, 2-amino butanoic acid and 2-amino pentanoic=20
acid, were found to be racemates. In addition, L-excesses were observed =

in 2-amino-2,3-dimethylbutanoic acid and 2-amino-2-methylhexanoic acid=20
from both the Murchison and Murray meteorites. The L-excesses observed=20
in the amino acids from Murray were smaller than those found in their=20
Murchison analogues. The substantial excess of L-alanine reported by=20
others was not observed in fractionated (reverse-phase chromatography)=20
extracts of either Murchison or Murray. Several amino acids were=20
identified in the Murchison extract that can interfere with=20
determination of the alanine enantiomer ratio on Chirasil-L-Val unless=20
removed by a prior fractionation step. The role of ultraviolet=20
circularly polarized light in generating meteorite enantiomeric=20
excesses and the possible significance of such excesses to the origin=20
of terrestrial homochirality are discussed. (C) 1999 COSPAR. Published=20
by Elsevier Science Ltd.


THE CAMBRIDGE-CONFERENCE NETWORK (CCNet)
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