STARDUST: The Risk Factor
The idea of collecting micro-particles from
our solar system was a concept, Drs. Donald Brownlee from the University
of Washington and Peter Tsou from the Jet Propulsion Laboratory (JPL)
have been working on since the early 1980's. Awarded in 1994, Stardust
personnel began designing and building this historic mission to rendezvous
with a comet and return particles back to Earth almost seven years after
On January 15, 2006 after traveling approximately 2.9 billion
miles, the 101-pound sample return capsule (SRC) will jettison back to
Earth for a dramatic night return.
The sample return capsule will
be released on a straight entry, descent, and landing path to the planned
landing ellipse (or footprint) in the Utah Test and Training Range just
outside of Salt Lake City.
In 2004, Genesis, a sister mission of Stardust
accomplished this similar return concept by jettisoning a SRC four-times
the mass of Stardust, marking it as the first NASA sample return mission
since Apollo in December 1972.
Due to a g-trigger based deployment circuit having been designed
incorrectly, Genesis' SRC parafoil did not deploy resulting in a hard-landing.
Despite the hard-landing it is expected that Genesis will recovery most of
its primary science data.
Thomas Duxbury, the Stardust Project Manager said,
"As we know, space exploration is difficult, pushing the boundaries
of technology and performing feats never attempted before. Stardust has
had a tremendously successful 7-year flight already, encountering the
asteroid Annefrank and surviving flying through the coma of comet Wild
2. The successes during these flybys were unprecedented and the data already
returned has revolutionized our thoughts on comets. Our last feat will
be to land in the desert of Utah and recover the cometary dust samples
captured during the Wild 2 flyby. While expecting a soft landing we are
preparing for a hard landing knowing that, even under this condition,
we expect to recovery the cometary samples for mission success. We now
eagerly await the delivery of our return capsule to Utah Test and Training
Range to see if it were sent via normal or express mail."
Stardust is returning to what was once part of the Great Salt Lake (now referred
to the Old Salt lake). This open area is now shared by the U. S. Army
and U.S. Air Force and is used primarily as a test and training range.
In order to ensure safety of base personnel and citizens in surrounding
areas, Stardust works landing probabilities within
the landing ellipse and possibility of the SRC returning into a populated
area. These calculations are done regardless of whether an area is occupied
by millions or one.
missions are required to conduct extensive testing before launch. Many of the instruments
are individually tested in the environment that spacecraft engineers expect
they will encounter. The entire spacecraft is put through vibration testing
to ensure it is able to survive the g-forces at the time of launch aboard
Boeing's Delta 2 rocket.
"It's a very similar concept to if someone
were to sky dive," says Mission Systems Manger, Edward Hirst. "Imagine
packing your recently used parachute, putting it on the shelf for seven
years and then picking it up expecting it to work after storing it for
that long. You need to have the confidence that your flight plan was
and is still valid, your equipment was packed properly and will still be in
working order as when it was last checked."
Stardust personnel have begun
the task of double-checking all data, mission concepts, and re-evaluating
previous testing to ensure maximum success. On January 15, 2006, the Stardust
team will have every expectation that its our efforts will pay off and
that the sample return capsule will return to Earth as planned. The excitement
and anticipation from all Stardust personnel, mission partners, and science
team is apparent. Through the numerous educators, museums and planetariums,
and other outreach partners - all eyes will be on Stardust less than
a year from now.
|Last updated January