baalke@mars.jpl.nasa.gov (Ron Baalke) (11/06/90)
ULYSSES MISSION STATUS November 5, 1990 Today, the Ulysses spacecraft is about 18 million miles from Earth, and traveling at a heliocentric velocity of about 88,000 miles per hour. With the completion of the spacecraft's second trajectory correction maneuver last week, instrument switch-ons and tests are the chief scheduled events for the Ulysses mission in the days ahead. In the trajectory maneuver, on Friday, November 2, the spacecraft fired its thrusters for 1 hour, 43 minutes to adjust the aim point for its flyby of Jupiter in February 1992. On Sunday, November 4, the spacecraft's 7.5-meter (24.3-foot) axial boom -- which serves as an antenna for Ulysses's Unified Radio and Plasma-Wave experiment -- was deployed. Following that deployment, flight controllers noticed a slight wobble in the spacecraft as it rotated on its spin axis. Small wobbles are expected to result when onboard equipment is activated, and generally are minimized by a system called a nutation damper. Nevertheless flight controllers were investigating the condition and possible corrective actions. The motion -- totaling 0.4 degree -- does not affect spacecraft operation or radio communication. Today, plans call for the Solar Wind Ion-Composition Spectrometer to be turned on. On Thursday and Friday, November 8-9, tests of the spacecraft's tape recorder will be conducted. On Friday, November 9, the Solar X-ray and Cosmic Gamma Ray experiment will be turned on. Instrument tests will continue Saturday, November 10, followed by relatively quiet monitoring Sunday and Monday, November 11-12. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 |