This Week on Galileo
January 21-27, 2002
Galileo Settles Down After The Io Flyby Last Week
This week sees the quiet murmur of cruise activities overtake the Galileo
spacecraft once again. The hectic week of the encounter, the safing, and
the recovery has passed, and the flight team turns its attention towards
the next and final target, Amalthea, in November.
On Monday, another opportunity to execute an orbit trim maneuver passes
unused. A maneuver opportunity is scheduled 3 to 4 days after a close flyby
to clean up any inaccuracies in the trajectory that may have accumulated
during the flyby. The final placement of the spacecraft at this encounter
was just 1.5 kilometers (less than one mile) higher than our targeted 100
kilometers (62 miles), and just 5 seconds later than desired, which was
well within the limits of our uncertainties. We are now assured that, even
if we perform no other maneuvers, the Galileo spacecraft will correctly
plunge into Jupiter's atmosphere in September 2003, fulfilling our
responsibilities for planetary protection of Europa. Galileo's discovery of
a probable subsurface ocean of liquid water on that icy moon leads to the
possibility that that environment could harbor life. It is our
responsibility, therefore, to make sure that the unsterilized Galileo
spacecraft cannot possibly crash into that satellite in the future,
potentially contaminating the environment with terrestrial microorganisms.
Also on Monday, routine maintenance of the spacecraft propulsion system is
Throughout the week the Fields and Particles instruments (Dust Detector,
Energetic Particle Detector, Heavy Ion Counter, Magnetometer, Plasma
Subsystem, and Plasma Wave Subsystem) are collecting continuous real-time
science. This continues a survey that began January 4 and will extend until
Sunday. At that time, the magnetospheric survey will stop, and playback of
the data that was recorded during last week's flyby will begin.
On Friday, the Extreme Ultraviolet Spectrometer turns its power on and
begins another extended examination of the hydrogen gas that fills the
space between the planets.