PLEASE NOTE:


*

CCNet DIGEST, 11 January 1999
------------------------------------------------

(1) NEWS REPORT ON ALASKAN FIREBALL
      Steven Excell <excell@cris.com>

(2) METEORITE IMPACT IN PORTUGAL
      J al Silva <joaolealsilva@mail.sonet.pt>

(3) STARDUST MISSION SET TO BRING BACK A PIECE OF A COMET
      Ron Ballke <BAALKE@kelvin.jpl.nasa.gov> wrote:

(4) IS LIFE A FLUKE?
      Andrew Yee <ayee@nova.astro.utoronto.ca>

(5) HOW NEAR WAS SAVED
      Andrew Yee <ayee@nova.astro.utoronto.ca>

(6) NASA - NAMN COOPERATION ANNOUNCED
     Mark Davis <MeteorObs@charleston.net>

(7) NEAR PEEP SHOW OF EROS AVAILABLE
      Ron Baalke <BAALKE@kelvin.jpl.nasa.gov> wrote:


=============================
(1) NEWS REPORT ON ALASKAN METEORITE IMPACT

From Steven Excell <excell@cris.com>

Anchorage Daily News, Sunday, January 10, 1998:

"Great ball of fire - Flash in sky likely exploding meteor"

By ELIZABETH MANNING
Daily News reporter

A brilliant flash and earthshaking boom noticed by thousands of Alaskans late
Friday were likely a meteor exploding in Earth's atmosphere, scientists said
Saturday.

Donald Martins, an astronomy professor at the University of Alaska Anchorage,
wasn't lucky enough to see the object that streaked blue, green and red across
the Southcentral Alaska sky. But based on witness accounts, Martins and other
scientists believe the flash came from a meteor or comet fragment - probably
the size of a pumpkin - that exploded about 50 miles above Earth's surface.

"That's almost certainly what it was," Martins said. "They aren't uncommon.
But it is very rare to have one explode and hear it."

Dozens of people phoned authorities late Friday to report the event, which
happened about 10:25 p.m. Most eyewitnesses described a brilliant and colorful
flash, followed several minutes later by a boom. The boom was so loud it shook
houses in Palmer and Wasilla and was heard from South Anchorage to Sutton and
beyond.

"I wish I could describe it," said Gina Gilmore, who watched the fireball from
a hot tub near Palmer. "It was an eerie blue and green color and lit up the
whole area. Then we heard an explosion, and it stilled our conversations."

Gilmore said she thought at first that the object was a shooting star or
meteor, but its intensity made the group in the hot tub wonder: Could it have
been a missile, an electrical explosion or something from the "X-Files"?

"It was greenish, and it was loud," said Rachael Wagner, 16, another observer
from Wasilla. She was inside her home and noticed the flash through the
window.

Assuming the object was a meteor, Martins said, it's possible that the
fireball was part of the Quandrantid meteor shower, which was expected to be
active from Dec. 28 through Thursday. On Tuesday, Anchorage residents reported
an object streaking low in the sky across the backdrop of the Chugach
Mountains.

The Quandrantids are one of the year's most intense meteor showers but are
among the least observed because of their location high in the Northern sky.
The meteors appear to emanate from the obsolete constellation Quadrans
Muralis, hence the name Quandrantids.

Though the origin of the Quandrantids is unknown, most meteor showers are
caused by fragments of comets - dust and ice debris - that boils away from a
comet's nucleus when it passes close to the sun. A meteor shower results when
Earth passes through a comet's debris stream.

Martins said most meteors burn up from friction as they enter Earth's
atmosphere. When the chunks are large enough, they sometimes explode
because the core of the object is much cooler than the outside.

"Imagine a cold rock coming in and getting very hot," said Greg Durocher, a
scientist with the U.S. Geological Survey. "It's under tremendous stress."

Durocher and other observers of the fireball said they heard the boom about
three or four minutes after they saw the flash. Based on that information,
Martins estimated that the object was about 50 miles away at the time of the
explosion.

The noise people reported may have been a sonic boom. However, a single noise
heard at the same time by everyone would indicate an explosion, he said.

Martins said he once heard of a fireball so loud it almost deafened several
fishermen in the South Pacific.

Although the object may have been fairly large for a meteor, Martins said, it
is unlikely that anyone will find a meteorite, which is a fragment of a meteor
that falls to Earth.

There were rumors Friday of objects striking the Parks Highway at Mile 141 and
reports by pilots of debris falling, but meteorites are extremely hard to
find, Martins said.

"Unless you can actually determine where the impact occurred, you're worse off
than finding a needle in a haystack," he said.

And if the object was part of a comet, Martins said, most of the fireball was
probably composed of ice, which would have melted before hitting the ground.
Martins said the colors people described suggest that the fragment was part of
a comet.

"It had a good tail on it," Gilmore said. "And it was amazing to watch it
going across the sky. I probably won't ever see that again."

* Reporter Elizabeth Manning can be reached at emanning@adn.com

Copyright 1999, Anchorage Daily News

==================
(2) METEORITE IMPACT IN PORTUGAL

From <joaolealsilva@mail.sonet.pt> [as posted on the metorite-list]

Hi.

Last December, around new year's eve, a meteorite impacted the south of
Portugal.

It made a small crater and it had around 30kg. Most off the pieces are gone
and the leftovers are already away to our natural history museum in Lisbon.

Anyway there is a work we would like to make, which is trying to
determinate the exact trajectory off this meteorite.

If by any chance some one saw in this days around 1 am the meteor we
would appreciate the information.

Thanks

JLS
Member off APAA ( Portuguese Amateur Astronomers Association )

==================
(3) STARDUST MISSION SET TO BRING BACK A PIECE OF A COMET

From Ron Ballke <BAALKE@kelvin.jpl.nasa.gov> wrote:

NASA's Stardust mission, scheduled for launch February 6, 1999 from Cape
Canaveral, FL, will send a spacecraft flying through the cloud of dust that
surrounds the nucleus of a comet - and, for the first time ever, bring
cometary material back to Earth.

Comets, which periodically grace our sky like celestial bottle rockets, are
thought to hold many of the original ingredients of the recipe that created
the planets and brought plentiful water to Earth. They are also rich in
organic material, which provided our planet with many of the ready-to-mix
molecules that could give rise to life. They may be the oldest, most
primitive bodies in the solar system, a preserved record of the original
nebula that formed the Sun and the planets.

"Scientists have long sought a sample directly from a known comet because of
the unique chemical and physical information these bodies contain about the
earliest history of the solar system," said Dr. Edward Weiler, NASA's
associate administrator for space science. "Locked within comet molecules
and atoms could be the record of the formation of the planets and the
materials from which they were made."

Stardust is the first U.S. mission dedicated solely to a comet and will be
the first to return extraterrestrial material from outside the orbit of the
Moon. Stardust's main objective is to capture a sample from a well-preserved
comet called Wild-2 (pronounced "Vilt-2").

The spacecraft will also collect interstellar dust from a recently
discovered flow of particles that passes through our solar system from
interstellar space. As in the proverbial "from dust to dust," this
interstellar dust represents the ultimate in recycled material; it is the
stuff from which all solid objects in the universe are made, and the state
to which everything eventually returns. Scientists want to discover the
composition of this "stardust" to determine the history, chemistry, physics
and mineralogy of nature's most fundamental building blocks.

Because it would be virtually impossible to equip a spacecraft with the most
sophisticated lab instrumentation needed to analyze such material in space,
the Stardust spacecraft is more of a robotic lab assistant whose job it is
pick up and deliver a sample to scientists back on Earth. The spacecraft
will, however, radio some on-the-spot analytical observations of the comet
and interstellar dust.

"The samples we will collect are extremely small, less than a micron, or
1/25,000th of an inch, in size, and can only be adequately studied in
laboratories with sophisticated analytical instruments," said Dr. Donald C.
Brownlee of the University of Washington, principal investigator for the
Stardust mission.

"Even if a ton of sample were returned, the main information in the solids
would still be recorded at the micron level, and the analyses would still be
done a single grain at a time." Stardust will meet up with Comet Wild-2 on
January 2, 2004. A gravity assist flyby of Earth will put Stardust on a
trajectory that will allow it to capture cometary dust intact at a low
relative speed of 6.1 kilometers per second (about 13,600 miles per hour).
An onboard camera will aid in navigating the spacecraft as close as about
150 kilometers (100 miles) from the comet's nucleus, permitting the capture
of the freshest samples from the heart of the comet.

Dressed for survival behind armored shields, Stardust will document its
10-hour passage through the hailstorm of comet debris with scientific
instruments and the navigation camera. On approach to the dust cloud, or
"coma," the spacecraft will flip open a tennis-racket-shaped particle
catcher filled with a smoke-colored glass foam called aerogel to capture the
comet particles. Aerogel, the lowest-density material in the world, has
enough "give" in it to slow and stop particles without altering them too
much. After the sample has been collected, the aerogel capturing device will
fold down into a return capsule, which closes like a clamshell to enclose
the sample for its safe delivery to Earth.

In addition, a particle impact mass spectrometer will obtain in-flight data
on the composition of both cometary and interstellar dust, especially very
fine particles. The optical navigation camera should provide excellent
images of the dark mass of the comet's nucleus. Other equipment will reveal
the distribution in both time and space of coma dust, and could give an
estimate of the comet's mass.

On January 15, 2006, a parachute will set the capsule gently onto the salt
flats of the Utah desert for retrieval. The scientifically precious samples
can be studied for decades into the future with ever-improving techniques
and analysis technologies, limited only by the number of atoms and molecules
of the sample material available. Many types of analyses now performed on
lunar samples, for example, were not even conceived at the time of the
Apollo missions to the Moon.

Comets are small, irregularly shaped bodies composed of a mixture of grains
of rock, organic molecules and frozen gases. Most comets are about 50
percent water ice. Typically ranging in size up to about 10 kilometers (6
miles) in diameter, comets have highly elliptical orbits that bring them
close to the Sun and then swing them back out into deep space. They spend
most of their existences in a deep freeze beyond the orbit of Pluto - far
beyond the Sun's dwindling influence, which is why so much of their original
material is well-preserved.

When a comet approaches within about 700 million kilometers (half billion
miles) of the Sun, the surface of the nucleus begins to warm, and material
on the comet's nucleus heats and begins to vaporize. This process, along
with the loss of rocky debris or other particles that fly off the surface,
creates the cloud around the nucleus called the coma. It is the glowing,
fuzzy coma that appears as the head of a comet when one is observed from
Earth. A tail of luminous debris and another, less apparent, tail of gases
flow millions of miles beyond the head in the direction away from the Sun.

Comet Wild-2 is considered an ideal target for study because, until
recently, it was a long-period comet that rarely ventured close to the Sun.
A fateful pass near Jupiter and its enormous gravity field in 1974 pulled
Comet Wild-2 off-course, diverting it onto a tighter orbit that brings it
past the Sun more frequently and also closer to Earth's neighborhood.
Because Wild-2 has only recently changed its orbit, it has lost little of
its original material when compared with other short-period comets, so it
offers some of the best-preserved comet samples that can be obtained.

Stardust was competitively selected in the fall of 1995 under NASA's
Discovery Program of low-cost, highly focused science missions. As a
Discovery mission, Stardust has met a fast development schedule, uses a
small Delta launch vehicle, is cost-capped at less than $200 million, and is
the product of a partnership involving NASA, academia and industry.

Principal investigator Brownlee is well-known for his discovery of cosmic
particles in Earth's stratosphere known as Brownlee particles. Dr. Peter
Tsou of NASA's Jet Propulsion Laboratory, Pasadena, CA, an innovator in
aerogel technology and maker of aerogel, serves as deputy investigator. JPL,
a division of the California Institute of Technology, manages the Stardust
mission for NASA's Office of Space Science, Washington, DC. Dr. Kenneth L.
Atkins of JPL is project manager. The spacecraft is designed, built and
operated by Lockheed Martin Astronautics, Denver, CO. JPL provided the
spacecraft's optical navigation camera, and the Max Planck Institute of
Germany provided the real-time dust composition analyzer.

Extensive information on the Stardust mission is available on the
Stardust home page:

http://stardust.jpl.nasa.gov

======================
(4) IS LIFE A FLUKE?

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

News Services
University of Arizona

Contact(s):

Neville J. Woolf, 520-621-3234, nwoolf@as.arizona.edu
J. Roger Angel, 520-621-6541, rangel@as.arizona.edu
James H. Burge, 520-626-7356, jburge@as.arizona.edu

January 9, 1999

Life a fluke? Telescopes will tell

AUSTIN, TX -- A planned telescope called the Terrestrial Planet Finder and
its successors will search planetary atmospheres for tell-tale signatures of
life -- and biologists and astronomers should collaborate in the hunt, an
astronomer from The University of Arizona in Tucson said today (Jan. 9).

"If all Earth-like planets eventually develop life, we may expect that about
half of them will show an ozone signature, because buildup of an oxygen
atmosphere is slow -- at least it was on Earth," said UA astronomy Professor
Neville J. Woolf . "If life development is difficult, then we will find many
Earth-like planets, but none of them will show an ozone signature," he added.

"One proviso is that a hotter planet like Venus did develop an ozone signature
in the past that likely existed for one two-hundredth of Venus' lifetime.
Fortunately, we can distinguish Venus-like planets because they are closer to
their stars than Earth is to our sun."

Woolf is presenting a poster paper titled "The Observational Problem of
Whether Life on Earth is a Fluke" on Saturday morning, Jan. 9, at the
American Astronomical Society meeting in Austin, Texas. His is giving the
presentation in conjunction with related sessions he organized or helped
present at the meeting earlier in the week. These were a program titled "An
Evening with the Terrestrial Planet Finder Project" and sessions titled "The
Astronomy Biology Connection."

Woolf is part of the Terrestrial Planet Finder project for the NASA Origins
program. In association with other UA astronomers, including Regents'
Professor of astronomy Roger Angel and James Burge of the Steward
Observatory, Woolf has proposed the construction of a linear nulling
interferometer for the detection of extra-solar Earth-like planets whose
planetary atmospheres bear gases indicative of life. It would be based in
space one astronomical unit from Earth.

The linear nulling interferometer is essentially a four-mirror device that
determines planetary position, atmospheric emission spectrum and surface
temperature. Four mirrors are spread evenly along a straight line for the
detection of radiation. The mirrors, because of their arrangement, block out,
or "null" the light from a star so astronomers can observe the surrounding
space for Earth-like planets. The design defeats one of the major difficulties
in detecting such planets -- the fact that the planets like ours are ten
million times dimmer than their suns.

The Terrestrial Planet Finder will separate the bands of the spectrum and map
the sky in each band, as well as measure surface temperature. In particular,
the linear nulling interferometer will search for the presence of carbon
dioxide, ozone and water in planetary atmospheres. The substantial presence
of all three gases would show that microorganisms live on the planet, Woolf
said.

He noted that the technology needed for this project is similar to the
technology for the Next Generation Space Telescope (NGST), so the proposed
date for construction of the Terrestrial Planet Finder project in 2007 is
feasible. Speedy development depends on advances in both nulling and mirror
technology, he added. Astronomers at the UA Steward Observatory have
successfully produced small-scale model mirrors, and they currently work on
a 2-meter NGST mirror prototype for smaller, thinner space-telescope mirrors
that cost only a fraction of the cost of the Hubble Space Telescope mirror.

The Terrestrial Planet Finder project is important for biologists as well as
astronomers, Woolf emphasized. "Biologists would be keenly interested in the
discovery of life on an extra-solar planet. And if that life operates with
very different chemistry than most life at Earth's surface, that would be
extremely interesting."

"The discovery of life on another planet may arguably be the crowning
achievement in the exploration of space," Woolf and Angel wrote in an article
"Searching for Life on Other Planets," published in the April 1996 Scientific
American.

"Finding life elsewhere, NASA administrator Daniel S. Goldin has said, (and
they quoted in the article) 'would change everything -- no human endeavor or
thought would be unchanged by that discovery.' "

LINKS:
http://athene.as.arizona.edu:8000/caao/
http://www.as.arizona.edu/


==========================
(5) HOW NEAR WAS SAVED

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

News Service
Cornell University

Contact: Blaine P. Friedlander, Jr.
Office: (607) 255-3290
E-Mail: bpf2@cornell.edu

FOR RELEASE: Jan. 8, 1999

How a down-to-the-wire computer fix at Cornell enabled a troubled spacecraft
to take images of an asteroid

ITHACA, N.Y. -- Some 240 million miles from Earth, a spacecraft hurtled
through the black void of space, off its intended course. But thanks to the
creation of a last-minute fix by Cornell University mission engineers during
a tense 24 hours just before Christmas, the $150 million mission now has
hundreds of new images of a distant asteroid.

The Near Earth Asteroid Rendezvous (NEAR) had almost been given up for dead
after a signal failure Dec. 20, but after contact was renewed scientists
quickly had to formulate a new mission plan. Thanks to the considerable
ingenuity of researchers at Cornell, NASA's Jet Propulsion Laboratory (JPL)
in Pasadena, Calif., and Johns Hopkins University's Applied Physics
Laboratory (APL) in Baltimore, signals were sent enabling the spacecraft to
capture images as it approached the asteroid 433 Eros. But it was
touch-and-go.

Cornell astronomy professor Joseph Veverka leads the mission's science team
in charge of the visual light camera and near-infrared spectrometer, two of
the five science instruments carried by NEAR. His operations team here
designs the spacecraft command sequences that point and operate the
instruments. NEAR's primary mission is to remain in orbit around Eros for
one year collecting high-resolution images and other science data.

The drama began Sunday, Dec. 20, when a signal was sent from APL to
implement a main engine burn to reduce the spacecraft's speed from 2,180 to
700 miles per hour on its approach to Eros. This was to be followed by three
additional burns to further reduce the speed to 11 miles per hour relative
to Eros and enable the spacecraft to go into orbit around the asteroid Jan.
10. But the first engine burn went awry.

When the first main engine burn began, the spacecraft's built-in safety
devices detected a problem and shut down the burn after one second. The
spacecraft began to tumble violently, and onboard communications systems
also were shut down. Contact between scientists and NEAR was lost for 36
hours. Instead of closing in on Eros at a relatively slow pace, the
spacecraft continued to speed along at more than 2,000 miles an hour.

"Afterward, it was Black Monday. We thought we had lost the spacecraft. We
thought that we had lost everything we had worked toward for the past four
years," says Ann P. Harch, a research support specialist in Cornell's
astronomy department, who designs command sequences to acquire camera and
spectrometer data.

The failure of the burn meant the postponement of NEAR's orbit of Eros until
next year. But mission scientists calculated that within about 60 hours NEAR
would pass Eros, about two weeks ahead of schedule.

Cornell engineers and astronomers with help from colleagues at APL cobbled
together a plan to salvage at least something from the flyby by commanding
NEAR to take photographs and infrared spectrographic images of Eros. But no
computer programs were available to send such commands.

"It was nerve-racking. We really weren't sure about the spacecraft. We
didn't know if this was perhaps our last and only chance to see Eros," says
Harch. "We really weren't sure if the main engine would burn or not."

For the impromptu Eros flyby, beginning at about 10:30 a.m. Eastern time
Dec. 23, Harch, Maureen Bell, also a member of Veverka's Cornell team, and
Scott Murchie of APL were asked at noon Dec. 22 to write a new, error-free,
computer command sequence for the spacecraft. The sequence would have to
slue the spacecraft to keep the instruments pointed continuously in the
vicinity of Eros throughout the flyby, while simultaneously keeping the
spacecraft's photovoltaic cells pointed toward the sun. Since Eros' location
was not known precisely, it would require taking a mosaic of four images to
guarantee capture of each view of Eros.

Harch had written the command programs for NEAR's flyby of asteroid Mathilde
in June 1997, a task that took her six months. But the new sequence would
have to be written in just 12 hours in order to reach the spacecraft in time
to make the complex onboard revisions.

Using electronic mail and constant phone conferencing, Harch and Bell at
Cornell kept in contact with Murchie in Baltimore, and with true grit, and
much sweat, the trio wrote the sequence. It was sent electronically to APL
in Baltimore close to midnight.

From midnight and into the morning hours, sleep-deprived APL scientists
tested the sequence for errors that could permanently incapacitate NEAR.
Then, the sequence was sent by microwave transmission to the craft during
the early morning hours Dec. 23. The "enable command" for the sequence was
sent at about 10 a.m. Eastern time and received by the craft at about 10:22
a.m., eight minutes before the first scheduled event in the imaging
sequence. Had the enabling command arrived eight minutes later, the
information would have been too late.

Then, more nail-biting. Scientists at Cornell, APL and JPL waited anxiously
to see if the program worked. If it didn't, the scientists would have to
wait until the rescheduled February 2000 rendezvous with Eros..

Hours later, Harch received an e-mail from Mark Robinson of Northwestern
University, a member of imaging science team: "We have an asteroid! ...
Here's a cut-out (partial frame) of M0089838063-F0-s showing 'Christmas
Dinner!'"

Editors: A composite photo of several views of Eros from the NEAR spacecraft
is available in the online version of this release at
http://www.news.cornell.edu/releases/Jan99/NEAR.pix.bpf.html

Related World Wide Web sites: The following sites provide additional
information on this news release. Some might not be part of the Cornell
University community, and Cornell has no control over their content or
availability.

Johns Hopkins Applied Physics Laboratory, http://www.jhuapl.edu/

Jet Propulsion Laboratory, http://www.jpl.nasa.gov/

Official NEAR Mission site, http://near.jhuapl.edu/

===================
(6) NASA - NAMN COOPERATION ANNOUNCED

From Mark Davis <MeteorObs@charleston.net>

NASA - NAMN Cooperation Announced

I am pleased to announce that the groundwork for a cooperative effort
between NASA's Space Sciences Laboratory and the North American Meteor
Network has been laid. Located at the Marshall Space Flight Center, the
mission of the Space Sciences Laboratory is to "plan, coordinate, direct,
and conduct original and supporting theoretical, experimental, and
observational research in a number of research areas, including
astrophysics, microgravity science, and Earth science." The North American
Meteor Network, an affiliate of the American Meteor Society, will be
assisting the Space Sciences Lab by providing visual meteor data.

Dr. Tony Phillips (NASA) and I have discussed projects in which
our extensive network of our observers, and their data, can be of the most
benefit. At present these include providing data for attempts at orbital
refinement on select meteor streams and the monitoring of the sporadic
background component. Other projects may be added in the future.

Additional information and updates will be provided as soon as they are
available. For information on how to become involved in meteor observing, or
how to hone your observing skills for these new projects, please contact me
at the address below.

Clear skies!

Mark Davis, MeteorObs@charleston.net
Mt. Pleasant, South Carolina, USA
Visual Program Coordinator
North American Meteor Network & American Meteor Society

NAMN:   http://medicine.wustl.edu/~kronkg/namn.html
AMS:    http://www.serve.com/meteors
=======================================================
(7) NEAR PEEP SHOW OF EROS AVAILABLE

From Ron Baalke <BAALKE@kelvin.jpl.nasa.gov> wrote:

NEAR image of the day for 1999 Jan 08
http://near.jhuapl.edu/iod/000/index.html

Two Views of Eros

This pair of images of the asteroid Eros was acquired by the Near Earth
Asteroid Rendezvous (NEAR) spacecraft on December 23, 1998, as the spacecraft
flew by the night side of the asteroid at a distance of 2300 miles (3800
kilometers) at 1:43 PM EST. These views, taken at 1:44 PM and 2:05 PM EST as
the spacecraft range increased from 2300 miles to 2500 miles (4100
kilometers), show only a tiny portion of the day side of Eros (phase angle
~119). The smallest resolved detail is approximately 1300 feet (400 meters)
across.

A firing of the main engine at 5 PM EST December 20, designed to slow the
spacecraft for insertion into orbit around the asteroid, was aborted by the
spacecraft. Contact with ground controllers was temporarily lost, but was
regained at 8 PM EST December 21 when autonomous spacecraft safety protocols
took over and transmitted a signal to the ground. All spacecraft systems were
determined to be healthy and operational. Within hours, a flyby observation
sequence was developed and uploaded to the spacecraft. 1026 images were
acquired by the multispectral imager, to determine the size, shape,
morphology, rotational state, and color properties of Eros, and to search for
small moons. The infrared spectrometer measured spectral properties of the
asteroid to determine what minerals are present, and the magnetometer searched
for a natural magnetic field. Analysis of the spacecraft radio signal will
yield bounds on the asteroid's mass and density.

The main engine was fired successfully on January 3, 1999, placing NEAR
on-course for a February 2000 rendezvous. Eros is NEAR's second asteroid
encountered. On June 27, 1997, NEAR flew by the main-belt asteroid Mathilde at
a range of 1212 kilometers (750 miles).

--------------------------------------------------------
Built and managed by The Johns Hopkins University Applied Physics Laboratory,
Laurel, Maryland, NEAR was the first spacecraft launched in NASA's Discovery
Program of low-cost, small-scale planetary missions. See the NEAR web page at
http://near.jhuapl.edu for more details.

----------------------------------------
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----------------------------------------
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Information circulated on this network is for scholarly and educational
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*

THE PROBLEM OF BACK CONTAMINATION FROM AN OPERATIONAL PERSPECTIVE

From E.P. Grondine <epgrondine@hotmail.com>

Benny -

      Some recent posts to the Conference have put forward several
hypothesis of the rather tentative sort on the nature of life in our
solar system as resembling hard facts.  First of these hypothesis was
that either life or its precursors originated on asteroids or comets,
and that these had then seeded both the Earth and Mars.  Next came the
hypothesis that impacts on the Earth and Mars had transported pieces of
rock carrying life forms from one planet to the other, and that these
life forms had survived the voyage.  While not explicitly stated, a
further hypothesis building on these, that these transfers had taken
place so recently that these life forms had not diverged, was implicit
in the statement that these transfers had "inoculated" the Earth
against back contamination by potentially hazardous life forms from
Mars.

     While not directly on the topic of castastrophism, the
contamination of the Earth's biosphere by an organism from Mars might
have truly catastrophic consequences, so perhaps some Conference members
may be interested in the following information on back contamination
problem from an operational perspective.  Here goes -

     In 1992 I attended the Eighth Congress of the Association of Space
Explorers in Washington, D.C.  Dr. Carl Sagan was the luncheon speaker,
and he shared with the assembled astronauts and cosmonauts his current
views on the evolution of Mars.  In Dr. Sagan's view, Mars would be an
ideal place to study the evolution of life, as he thought that life most
likely had evolved there, but then had been completely exterminated by
the evolution of Mar's atmosphere into a rain of hydrogen peroxide.  In
Dr. Sagan's view the astronauts would thus be able to look for fossils
without encountering the danger of being exposed to any living organism.

     At this time, while the Soviet Union had collapsed, the
Commonwealth of Independent States was still in the process of
formation, and serious economic collapse had not yet set in.  Russia had
at least 2 long range Marsokhod rovers set to go, with additional
follow-up rovers likely; Dr. Sagan and the attendees expected that the
question of life on Mars would receive a definite answer in the
immediate future.

    At the Congress, I had a chance to talk for nearly an hour with
Cosmonaut Konstantin Feoktistov, one of the lead engineers for the
Soviet manned Mars program, with Cosmonaut Georgi Grechko serving as
translator.  The Soviet manned Mars program was not merely a paper
program, but had started in 1961 as part of the distribution of tasks
between the N1 launcher team under Korolev at OKB-1 and the UR 700
launcher team under Chelomei and Glushko at Krunichev.  Since 1961
several nuclear thermal engines had been developed and had undergone
long duration test firings; a completely closed environmental system had
been constructed and had undergone 2 long duration tests; 3 different
manned Mars craft for launch by the N-1 rocket had been completely
designed; these designs had then been adapted for launch by the Energia
heavy lift launcher;  models of Mars entry craft had undergone
aerodynamic tests; cosmonauts had been put through extended periods of
weightlessness identical to those that would be encountered on a manned
Mars flight. This was no paper program, but one on which a sizable
amount of money had been spent.

      As the program had developed a serious problem had emerged:  The
possibility that the cosmonauts might be exposed and contaminated by a
Martian life form.  The solution that had been developed was as follows: 
The first flight of the manned Mars ship would merely be to Mars orbit,
with manned landings on the Martian moons of Phobos and Deimos.  The
cosmonauts would operate from Mars orbit a long range rover on the
surface, which would collect possible life bearing samples and deliver
them to a vehicle which would carry them up to the manned Mars ship. 
There the samples would be exposed to a chemical wash and radiation,
following which they would be studied to see if the remains of life
forms existed. As you can see, the problem was taken most seriously.  If
any life had survived and the crew were then exposed to it, both it and
they would be contained on board the ship, and the possibility of
bringing the surviving organisms back to Earth was set at zero.

      The Soviet Space Research Institutes' Phobos and Deimos probes and
their long range Marsokhod rovers may be viewed as unmanned precursor
missions to this manned mission.  Indeed, the Space Research Institute
had also looked at a sample return mission, but as one of the
participants in this put it to me, the problem of sample handling had
proved to be a real nightmare.  The containment mechanism itself stood
to be contaminated when storing the samples; finally, a device something
like a "Chinese Box" had been proposed, with each containment being
cleaner than the proceeding, down to an acceptable level of risk.

      This brings us to today, and the current NASA manned Mars effort. 
As I previously reported in my coverage of Dan Goldin's interview with
John McLaughlin, NASA Administrator Goldin has stated that he thinks
that manned flight to Mars may be possible by 2010.  While surprising to
some, this comes as little surprise to those familiar with Goldin's
start in the space program back in the 1960's as an engineer for a
proposed manned Mars craft to be launched by the Saturn 5 rocket..

      In recent testimony before the House Space Sub-Committee Goldin
re-iterated that his second priority after crew safety is to lower US
launch costs.  The X-33 project currently under development is a
technological test-bed for a Reusable Launch Vehicle (RLV), which it is
hoped will be made operational by about 2005.  It is hoped that this RLV
will be capable both of putting into orbit both large communication
satellites, and of servicing the International Space Station with both
manned and un-manned payloads.  As a back-up to the RLV, two Enhanced
Expendable Launch Vehicles (EELVs) are under development, as well as a
manned Crew Return Vehicle (CRV) for use with the EELVs for the
International Space Station.

     For the small satellites low end of the market (those used to put
into low Earth orbit the small satellites used for relay communication
systems like Iridium) NASA is supporting the development of small
launchers by private firms.    This leads to the question, "What becomes
of the Shuttle?"  The Shuttle isn't effective for the small payloads;
manned flight will be done with the RLV or EELVs, as well as large
communication satellites and reconnaissance satellites.

     It is now becoming clear that Goldin is hoping to convert the
Shuttle into a heavy lift vehicle, sometime after 2005.  By removing the
main engines from the shuttle and mounting them on a return shell, you
no longer have to put the mass of the shuttle's airframe into orbit for
each launch.  This variant, called Shuttle C, has already been not only
studied, but a return shell for the 2 engine variant has already been
designed and tested by Boeing. Furthermore, with a lift of 150 tons,
such a heavy lift vehicle is capable of putting into orbit a manned Mars
craft; and indeed, NASA has already developed a reference manned Mars
mission using 2 launches of this vehicle.    


     Additionally, Goldin has set out the cost limits for the manned
Mars mission. In a talk at the American Astronautical Society conference
held at Houston in November, NASA's John Lewis set them out as follows: 
Before Goldin will endorse it, the overall per-mission price has to be
$2 billion dollars, with foreign (either European, Japanese, or Russian)
interests picking up at least 25% of this, or $500 million dollars. 
Since the launch costs with the Shuttle C are significantly lower than
for the shuttle, around $120 million a piece or 2 for $240 million,
these numbers can be met, if the foreign partners join in.  Development
costs for the Shuttle C have been estimated at around $3 billion, and
spread out over a number of years could fit inside of the NASA budget.

     In sum, it is clear that Goldin wants to move NASA and the US
launch industry into a position such that a US President, speaking in
the year 2000, will be able to realistically propose the goal of placing
a man on Mars and returning him safely to the Earth before the end of
the decade (2010).  Goldin is relying upon political support for this
goal coming from the home states of the shuttle contractors in Florida,
California, Alabama, Texas, Mississippi, Washington, and other states.

     As this dream moves from paper to the drawing boards, NASA now
finds that it is hitting the same problem the Soviet scientists hit back
in 1970 or so: Is there any life on Mars, and how do you protect the
Earth from any danger it might present?  So far, a sample return mission
in cooperation with France, returning samples gathered by both US and
French craft is under development, and this will present the first test
case.
      At the ALH 84001 press conference I asked Dan Goldin about this
and he explicitly stated that he will allow NASA to do nothing that
might expose the Earth's biosphere to a potentially hazardous organism. 
Despite his assurances, the National Research Council has proposed that
the biological safety group be moved from out of NASA control and placed
in an independent oversight capacity. Given that the National Review
Council's panel had members from other US government agencies, you may
expect them to take stands on this matter shortly.  Indeed, since by
statute either the Centers for Disease Control, the National Institute
of Health, the Surgeon General, or the Army Biological and Chemical
Warfare Command could by themselves stop NASA in its tracks if they felt
that the situation warranted it, you may expect NASA to take very
careful measures in order to assure that they don't become involved.

      My understanding is that under the current scheme John Rummel,
former planetary biology officer for NASA, and now  of the Woods Hole
Oceanographic Institute, will be the planetary quarantine officer for
Mars, though I am sure that Dr. Morrison will be able to give us more
information on this.  Given the problems that have been caused by
organisms from East Europe, Asia, and South America which have been
introduced into US waters through the discharge of waters from
freighters from these areas, I expect the utmost care to be taken with
all Mars missions.

Best wishes -
EP



CCCMENU CCC for 1999

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The content and opinions expressed on this Web page do not necessarily reflect the views of nor are they endorsed by the University of Georgia or the University System of Georgia.