This Week on Galileo - March 23-27, 1998
Galileo spends the first five days of this week preparing for its next encounter with the Jupiter system, a flyby of Europa scheduled for Sunday, March 29, at an altitude of about 1,645 kilometers (1,022 miles). Preparations include processing and transmitting to Earth all remaining science information from the spacecraft's previous complete science encounter with the Jupiter system in December 1997. In addition, on Wednesday, the flight team completes constructing and transmits to the spacecraft the set of computer instructions required to perform the final flight path correction prior to the Europa flyby. The flight path correction is scheduled for execution on Thursday, three days prior to the close flyby. Also on Thursday, the flight team will transmit to the spacecraft the set of computer commands that will control all spacecraft activity during the encounter period. Finally, on Friday, regular maintenance is performed on the spacecraft's onboard tape recorder which is used to store all of the science information gathered during Galileo's encounters.
The science information that is processed and transmitted to Earth this week includes data from three observations: two by Galileo's near infrared spectrometer and one by its photopolarimeter radiometer. The first of the spectrometer data contains information further describing the surface composition on a region of Europa characterized by the much publicized wedge-like features. These features are believed to be evidence of the existence of a liquid ocean, or, at least, soft ice, under Europa's surface. Not unrelated to the possibility of a subsurface ocean, the photopolarimeter radiometer observation contains information on the temperature of the surface of Europa. The observation is part of a series designed for the Galileo Europa Mission to search for possible hot spots on Europa. These hot spots, if they are found, could be further evidence of a heat source on Europa that could lead to the creation of a liquid ocean or soft ice environment.=20 The second set of spectrometer data deviates from the Europa focus and contains data describing volcanic activity on Io. This data is important for keeping tabs on Io and will help scientists plan their observations later in the Galileo Europa Mission.
Don't forget that Galileo's next encounter starts this Saturday (28 March)! Come back then for the return of Today on Galileo.