There are several Ulysses home pages you can go to at JPL, and there are press releases to be found at JPL and at JPLs new products area. Descriptions of the various instruments are provided over at the JPL instruments page. The European Space agency has a gallery of images that are useful for seeing the spacecraft and its science mission. The above figure is from that archive and shows the high speed solar wind from the polar regions detected by the Ulysses spacecraft, superimposed on a SOHO/LASCO image of the solar corona.
The bottom line is that there are two instruments that can determine the speed of the solar wind by detecting specific tracer ions in the plasma. These are the SWOOPS 'Solar Wind Plasma Experiment' and the SWICS 'Solar WInd Ion Composition Experiment'. Both are equipped with electrostatic analyzers that can sense the charge state of the incoming particles in specific energy bands which is read out every 8 minutes. The SWICS instrument is also equipped with a 'time-of-flight' sensor. These are devices that provide two or more pulses as the particle enters the detector and leaves the detector. By measuring the time between the pulses over the fixed distance in the detector, the speed of the particle can be derived over a range from 175 to 1280 kilometers/sec.
Copyright 1997 Dr. Sten Odenwald
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