[meteorite-list] Finding the Origin of the Solar System through Stardust

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri Dec 16 11:17:43 2005
Message-ID: <200512161615.jBGGFke17849_at_zagami.jpl.nasa.gov>

http://www.lacanadaonline.com/articles/2005/12/15/news/lnws-jpl1215.txt

Finding the Origin of the Solar System through Stardust
By Mary O'Keefe
La Canada Valley Sun
December 16, 2005

So all JPL's Stardust spacecraft has to do is fly close behind a comet,
collect dust particles and rocks from its tail, and return to Earth with
those samples so scientist can study the origin of the Universe. Just
your normal, everyday science fiction turn reality type of thing they do
at JPL.

For over seven years the Stardust spacecraft has traveled over billions
of miles in space. It encountered the tail of Comet Wild 2, collected
material, and will land in the Utah desert on January 15, 2006.

"The material is frozen in time," said Tom Duxbury, Stardust project
manager at JPL.

The material is particles from the tail and coma of Comet Wild 2. The
jets of material spewing out as the comet travels through space. The
jets will force material from the nucleus of the comet toward the sun
then the solar winds blow it back away from the sun, explains Duxbury.
The Stardust spacecraft, flying within 147 miles of the comet, retrieved
material as it was going toward the sun.

"It was real fresh stuff," Duxbury said.

The spacecraft can hold on to the dust and rock particles thanks to
Aerogel, a silicon-based solid with a porous, sponge-like structure that
is 99.8 percent air and 0.2 percent silica dioxide. It was discovered by
chemist Samuel S. Kistler in the late 1930s. It has been used by
NASA/JPL for spacecraft insulation on the Mars Pathfinder mission and
for the Stardust mission. It was prepared and flight qualified at JPL.
The particles from Comet Wild 2 decelerate as they bore deeper into the
threadlike silica of the Areogel, allowing samples sustain minimal
damage while being collected.

Finding the perfect comet was not an easy task, however the nature of
the solar system gave scientists a little help.

"Comets travel at the far edge of the galaxy. Periodically some will fly
by a planet and it will be thrown closer to us [because of the planet's
gravity]," Duxbury said.

In 1974, when Wild 2 flew close to Jupiter, its gravity threw it into
the orbit of Mars.

"That placed the comet at our doorstep," Duxbury said. "The solar system
gave us a gift."

Comets are important to study because they give us a glimpse into our
solar system's history. The material that will be brought back is
estimated to be 4.6 billion years old.

"[It is] the origin of our solar system," Duxbury said. "All planets,
asteroids, and the Sun are made of comets."

Cometary material condensed into commentary bodies, which condensed into
planets, Duxbury added. Comets are mostly made of water. It is thought
that most of the Earth's water was brought by comets. Scientist have
received some data by flybys of the comet.

"At first we thought comets were like dirty snowballs but based on fly
bys it is more like snowy dirtballs," Duxbury explained.

Duxbury will go to the Utah desert next week to join in an exercise
practicing the spacecraft's landing and retrieval.

"The moon will be at the same phase as the recovery on January 15,"
Duxbury said.

He is not concerned about the recent crash landing of Genesis. The
mission was to capture particles of the solar wind and bring them back
to Earth with a dramatic Hollywood ending. Stunt pilots trained to
capture the spacecraft with hooks before it fell to the ground. That
plan failed with the pilots not even getting a chance to try their
maneuver, the parachutes did not deploy correctly. The spacecraft made a
deep impression in the Utah desert floor, but some data was still able
to be retrieved and used in research. Duxbury said that they have
studied the errors of Genesis and are confident this will not happen to
their spacecraft.

The Stardust spacecraft is scheduled to reenter Earth's atmosphere and
touch down at approximately 3:15 a.m. January 15. The craft will be
taken to a clean room in a nearby hangar. The canister will not be
opened until it is at the curation facility at the Johnson Space Center
in Houston, Texas. Scientists from around the world can request samples
of the material for study through NASA.

At that point Duxbury's job will be completed and scientist study the
material will take over. After working at JPL for 40 years, Duxbury
takes it all in stride. Yet he can't help to emphasize how important
this mission can be to the study of the origin of the Earth and of the
solar system. He quotes from a fellow scientist, "We are all made of
stardust."
Received on Fri 16 Dec 2005 11:15:45 AM PST