This Week On Galileo - April 20-26, 1998
Galileo continues on the outbound leg of its orbit around Jupiter as it processes and transmits to Earth science information safely stored on the spacecraft's on-board tape recorder. The information was gathered by the spacecraft's 11 instruments as they flew past Jupiter and its moons late last month. On Thursday, the spacecraft performs a small turn to keep its antenna pointed toward Earth. These turns are required to maintain the right telecommunications conditions and science data flowing to the ground.
The batch of information processed and transmitted this week is dedicated primarily to observations of Jupiter's icy moon Europa. The spacecraft camera, or solid-state imaging subsystem, returns two pictures of Europa this week. The first is a high-resolution picture of a circular feature known as Tyre Macula. This feature is believed to have been created by the impact of a mountain-sized asteroid or comet. This region was imaged at lower resolutions during Galileo's primary mission in April 1997 and is scheduled for imaging again at the end of May. The other picture that is returned this week includes a region of bright plains that transitions to a series of wedge shaped features. The spacecraft's Near Infrared Mapping Spectrometer also returns two observations of the same region of Europa. The region is characterized by pull-apart wedges, but also contains dark spots.
Finally, continuing from previous weeks, is the return of science information from the fields and particles instruments describing the interaction of Jupiter's magnetosphere with Europa.