CASSINI - Flipped a Bit - Back to Normal and Ready for Enceladus

Cassini Back to Normal, Ready for Enceladus
Jet Propulsion Laboratory
November 24, 2010

http://www.jpl.nasa.gov/news/news.cfm?release=2010-398

NASA's Cassini spacecraft resumed normal operations today, Nov. 24. All
science instruments have been turned back on, the spacecraft is properly
configured and Cassini is in good health. Mission managers expect to get
a full stream of data during next week's flyby of the Saturnian moon
Enceladus.

Cassini went into safe mode on Nov. 2, when one bit flipped in the
onboard command and data subsystem computer. The bit flip prevented the
computer from registering an important instruction, and the spacecraft,
as programmed, went into the standby mode. Engineers have traced the
steps taken by the computer during that time and have determined that
all spacecraft responses were proper, but still do not know why the bit
flipped.

The flyby on Nov. 30 will bring Cassini to within about 48 kilometers
(30 miles) of the surface of Enceladus. At 61 degrees north latitude,
this encounter and its twin three weeks later at the same altitude and
latitude, are the closest Cassini will come to the northern hemisphere
surface of Enceladus during the extended Solstice mission. (Cassini's
closest-ever approach to the surface occurred in October 2008, when it
dipped to an altitude of 25 kilometers, or 16 miles.)

During the closest part of the Nov. 30 flyby, Cassini's radio science
subsystem will make gravity measurements. The results will be compared
with those from an earlier flyby of the Enceladus south pole to
understand the moon's interior structure better. Cassini's fields and
particles instruments will sample the charged particle environment
around Enceladus. Other instruments will capture images in visible light
and other parts of the light spectrum after Cassini makes its closest
approach.

The Cassini-Huygens mission is a cooperative project of NASA, the
European Space Agency and the Italian Space Agency. The Jet Propulsion
Laboratory, a division of the California Institute of Technology in
Pasadena, manages the mission for NASA's Science Mission Directorate,
Washington, D.C.

More Cassini information is available at http://www.nasa.gov/cassini and
http://saturn.jpl.nasa.gov.

Jia-Rui C. Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jia-rui.c.cook @ jpl.nasa.gov

Enormous Bit-Flipping Thank You to Ron Baalke of sci.space.news !

Happy days *and*...
Starry, starry nights !

--
Tender is my love for thee
Oh! Star so close at hand,
Warming those so dear to me
As we play on the sand.

It's so easy to believe
In all this beachin' fun,
Someday you and we will be
Altogether one.

http://www.swpc.noaa.gov/primer/primer.html

As it sinks into the sea,
You almost hear the SSSSSSSun...

http://tinyurl.com/beachsunsetjpg

Indelibly yours,
Paine Ellsworth

PS - http://painellsworth.net !
http://www.secretsgolden.com !
http://en.wikipedia.org/wiki/User:Paine_Ellsworth !