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Stardust Mission

With all the attention that Comet Hale-Bopp is getting, the Stardust project
has put out this press release.  As most members of this list probably 
already know, the CI meteorites are suspected of originating from comets due 
to their primitive makeup and high water content.   Well, we will be launching
a spacecraft, Stardust, that will collect dust particles from Comet
Wild 2 and return them back to Earth.  Analysis of these dust particles will
give us a great insight into what makes up a comet and will confirm
if certain types of meteorites, such as CI, really do come from comets.
I've started working on the Stardust project a couple of months ago, 
and I'll keep you abreast on the progress of the mission.

Ron Baalke

PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011

Contact:  Jane Platt

FOR IMMEDIATE RELEASE                            April 3, 1997


     Just as Comet Hale-Bopp continues its journey across the 
nighttime sky, another currently visible comet, Wild 2, is 
capturing the attention of NASA's Stardust Project for a vitally 
important reason.  

     Stardust, a spacecraft with a planned 1999 launch, will 
capture samples of comet dust from Wild 2 in 2004 for return to 
Earth in 2006.  This current appearance by Wild 2  (pronounced 
"Vilt 2"), offers the Stardust team a prime opportunity to 
prepare for the spacecraft's historic journey by gathering data 
on the comet's brightness and the size and quantity of its gas 
and dust particles. 

     The spacecraft is protected from oncoming cometary particles 
with a front "Whipple Bumper," a shield named for renowned 
astronomer Fred Whipple, with a composite structure that includes 
metals and several curtains of the same material as bullet-proof 
vests.  However, the bumper does not offer unlimited protection 
against a barrage of numerous, large particles.

     "We want to study the dust envelope of Wild 2 so we'll know 
how close we can fly without jeopardizing the spacecraft," said 
Stardust Project Manager Dr. Kenneth Atkins. "These current 
observations will help us significantly reduce the risk."

     By observing Wild 2 in both visible and infrared light, the 
Stardust team will be able to fine-tune models of the comet 
environment and mission logistics.  Final trajectory adjustments 
may be made up to a few hours before encounter, using 
observations made by Stardust en route to Wild 2.  That encounter 
will take place on January 2, 2004, about 98 days after the 
comet's perihelion, or closest pass by the Sun. During Wild 2's 
current visit, scientists will study the comet's activity at a 
comparable post-perihelion point, gathering data crucial to the 
success of the Stardust mission.     

     Wild-2 studies are being conducted at numerous 
observatories, including Lowell Observatory, Flagstaff, AZ; the 
Lunar and Planetary Laboratory, University of Arizona, Tucson; 
the W.M. Keck Observatory and other major telescopes atop Mauna 
Kea, HI; and the 200-inch Hale telescope at Palomar Observatory 
near San Diego, CA.  Amateur astronomers can see Comet Wild 2 
with a relatively small telescope through August, with the best 
viewing before the end of  May.  With an apparent magnitude of 
9.6, Wild 2 is currently visible almost directly overhead about 
one hour after sunset and is located in the constellation of 
Cancer close to the Praesepe open star cluster.

     Comet Wild 2, a short-period comet with a six-year orbit, 
was discovered in 1978 by the Swiss astronomer Paul Wild, after 
its close encounter with Jupiter in 1974.  This may have been the 
comet's first journey to the inner solar system in recent 
centuries, which means it is in a more pristine state than other 
comets which have been "around the block" more often.  For this 
and several other reasons, Wild 2 was chosen as the destination 
comet for Stardust.

     As Atkins explained, "Wild 2's orbit presents attractive 
features for doing a sample return.  The comet will be in the 
right place at the right time so that when Stardust encounters 
it, Wild 2 will have a relatively low flyby speed of 6 kilometers 
per second (3.7 miles).  This makes the task of catching the 
comet dust as it whizzes by much easier.  In addition, the 
orbital geometry of Wild 2 enables us to save money by launching 
Stardust on a Delta rocket and designing an efficient 

     To capture the comet dust without harming it, Stardust will 
use aerogel, a spongy, silica-based solid with 99 percent empty 
space.  The tiny cometary particles will bury themselves in the 
transparent aerogel, awaiting retrieval by scientists on Earth.  
On its way to Wild 2, Stardust will loop twice around the Sun and 
collect interstellar dust particles.  By returning these space 
and cometary materials to Earth, Stardust will mark the first 
space sample return mission since the Apollo missions collected 
moon rocks in the 1960s and 1970s.

     Stardust co-investigator Ray Newburn said comets are 
apparent leftovers from the formation of the solar system and may 
unlock many cosmic secrets.  As he put it, "Comets are a 
different sort of beast.  They've been in a cosmic deep-freeze 
for most of the solar system's 5-billion-year history.  Many 
scientists believe comets added complex organic molecules to the 
primordial soup of oceans that helped form life. Stardust should 
give us some hard facts about Wild 2 and other comets, including 
chemical composition and age." 

     Stardust is one of NASA's Discovery missions, which team the 
agency with industry and universities to launch low-cost 
spacecraft in a short time frame with highly-focused science 
goals.  Stardust's principal investigator is Dr. Don Brownlee of 
the University of Washington, Seattle, WA.

     The Stardust spacecraft and sample return capsule are being 
built by Lockheed Martin Astronautics in Denver, CO.  The mission 
is managed by NASA's Jet Propulsion Laboratory for  NASA's Office 
of Space Science, Washington, DC.  JPL is also developing the 
aerogel and the spacecraft's navigational camera, also to be used 
for scientific imaging.  Stardust's cometary and interstellar 
dust analyzer instrument is provided by Jochen Kissel through the 
Max Planck Institute in Germany; the University of Chicago, IL, 
is building a Whipple Shield dust impact counter.
     Additional information is available on the Stardust home 
page on the World Wide Web at: