PLEASE NOTE:


*
From:             Benny J Peiser <B.J.PEISER@livjm.ac.uk
Subject:          CC DIGEST 1/11/97
To:               cambridge-conference@livjm.ac.uk
Priority:         NORMAL

CAMBRIDGE-CONFERNCE DIGEST, 1 November 1997
 

(1)  DREADFUL SORRY, CLEMENTINE:  Washington brushes off the
 asteroid threat

(2) UA SCIENTIST HEADS TO ANTARCTICA AS PART OF METEORITE SEARCH
 TEAM

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

Partial text from Time Magazine, October 27, 1997:

DREADFUL SORRY, CLEMENTINE:  Washington brushes off the asteroid threat

Leon Jaroff

During the 3 or 4 billion years that it has existed on Earth, life as been
devastated, and on occasion nearly wiped out, by the explosive impact of
giant asteroids or comets.  Now terrestrial life has finally evolved to the
point where it is intelligent and capable enough to defend itself against
such threats from space -- if it has the will to do so.

That is why some scientists are so distressed by President Clinton's
line-item veto last week of the $30 million that Congress had allocated for
the Clementine II project next year.  Clementine is a spacecraft that was to
be launched in 1999 to approach an asteroid named Toutatis and send a
camera-equiped rocket barreling into it. . . . .

Reasons for the veto, an Administration spokeman explained, included
concern that the project might violate the Antiballistic Missile Treaty,
that it was a thinly-disguised supplement to other Pentagon projects and
more logically belonged in the NASA budget.  Another -- but unspoken --
reason, say scientists familiar with the budget debate, is the "giggle
factor", the tendency of many in government to scoff at the danger posed by
asteroids.

[A paragraph follows explaining the risk of impact]

In an attempt to assess the danger, a few dedicated astronomers have been
scanning the skies, borrowing time on large telescopes, building their own
detectors out of off-the-shelf parts and barely scraping by on the $1
million or so NASA contributes annually to the total effort.  Their goal is
to identify and determine the orbits of the still undiscovered near Earth
asteroids.  That would enable them to predict, sometimes many years in
advance, the possibility of a disastrous encounter.  Those predictions and
knowledge gained from missions like Clementine would give Earth's defenders
time to mount the appropriate defense, using missiles to deflect or destroy
a threatening intruder.

With a bit more funding and access to the Air Force's satellite tracking
telescopes, say astronomers, they could find and track the most threatening
asteroids within a decade.  The cost to taxpayers, they estimate, would be a
few million dollars more a year.  If you think of it as an insurance policy
for the entire planet, it's a small price to pay.

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

University of Arizona News Services

From: Lori Stiles, UA News Services, 520-621-1877,
lstiles@u.arizona.edu

Contact(s): Timothy D. Swindle, 520-621-4128,
timswindle@ccit.arizona.edu
 

October 29, 1997

UA SCIENTIST HEADS TO ANTARCTICA AS PART OF METEORITE SEARCH TEAM

Timothy D. Swindle has been studying meteorites for the past 15 years.
Now he's heading to Antarctica to hunt them.

By the time he hits the high, ice-desert polar plateau in December,
maximum daytime temperatures will hover between minus 20 degrees
and plus 10 degrees Fahrenheit. And this is summer, so the sun never
sets. Returning Antarctic meteorite hunters say they miss darkness, and the
color green. Why go?

"I have never found a meteorite. I have an urge to find a great
meteorite. And I get to go to a place that people who have visited say is
absolutely gorgeous," said Swindle, an associate professor of planetary
sciences at The University of Arizona in Tucson. He is on a team of eight
going to the South Pole as part of the 1997-98 Antarctic Search for
Meteorites program (ANSMET).

Swindle, 42, who joined the UA in 1986, specializes in analyzing the
noble gases in extraterrestrial materials to understand the chronology of
the solar system. His research projects include determining the ages of
impact craters, finding when the earliest solids formed in the solar system
and discovering when liquid water flowed on Mars.

Roughly 3,000 meteorites were known before 1976, when the National
Science Foundation Office of Polar Programs funded the first of its
annual ANSMET expeditions, Swindle said. ANSMET researchers since have
recovered another 8,000 meteorites. These are curated at the NASA
Johnson Space Center in Houston and ultimately belong to the
Smithsonian Institution. Scientists apply for ANSMET meteorite samples
for study to an NSF-funded committee of meteorite experts called the
Meteorite Working Group, a body on which Swindle has served.

ANSMET meteorites currently represent "the only reliable, continuous
source of new, non-microscopic extraterrestrial material, and will
continue to be until future planetary sample-return missions are
successful," said Ralph P. Harvey of Case Western Reserve University,
principal investigator of the ANSMET program. "Their continued
retrievel is the cheapest and only guaranteed way to recover new things from
worlds beyond the Earth," Harvey said in his extensive Web page at
http://www.cwru.edu/artsci/geolog/ANSMET/.

Swindle and Harvey talked about the possibility of Swindle joining an
ANSMET team a few years ago. Swindle was invited to join the 1997-98
team early this year. He quickly telephoned Guy Consolmagno of the
Vatican Observatory and the UA Steward Observatory, a member of the
1996-97 ANSMET team. Despite some illnesses, bad weather and a
greater-than-usual number of visits from film crews, Consolmagno and
his six colleagues collected 390 meteorites last year.

Swindle's team will fly from Christchurch, New Zealand, to McMurdo
Station, Antarctica, about Dec. 1. There they will pack all the food
stores and supplies they need for six weeks or more on the ice. Each
team member has his or her own snowmobile and at least two nansen
sledges piled high with supplies. Swindle and his teammates also put in a
few days' training on some necessary field routines -- pitching tents,
operating snowmobiles, and practicing crevasse rescues. There are
significant crevasse hazards surrounding potential meteorite-bearing fields.

After about a week at McMurdo, the expedition is flown a couple of
hundred miles inland to the meteorite stranding surface selected as the
season's field site. In Swindle's case, the target area is near Walcott
Neve, south of the Queen Alexandra Range in the 1,900-mile length of the
Transantarctic Mountains. Unofficially, this meteorite-rich hunting ground
is called "Foggy Bottom." The volume of ice flowing through the Walcott is
diminishing rapidly, according to Harvey. Aside from the meteorites it
offers, this area may be a useful example of how the East Antarctic ice
sheet is responding to climate change, Harvey noted in his Web page.

Antarctica is showered with no more meteorites than anywhere else on
Earth, Swindle said. But it's easy to spot rocks against blue-white
ice. Also, the East Antarctic ice sheet flows from the center to the
edges of the South Pole continent, and meteorites naturally collect
where the sheet flows against the mountains. The tell-tale signature of a
meteorite as opposed to a rock is a millimeter-thick black fusion crust that
covers the surface, Swindle said. The crust formed when the rock melted by
friction as it sailed through the Earth's atmosphere.

After six weeks on the East Antarctic ice sheet, Swindle said he's sure
he'll want to return to civilization, and, particularly, to his wife and two
kids.

But finding a special meteorite would be a worthwhile prize. The most
special meteorite to him would be a meteorite from Venus, Swindle said. He
and a student have thought about how a Venusian meteorite could be
identified. No one's found one, yet.



CCCMENU CCC for 1997