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The Cassini spacecraft is orbiting Saturn with a period of 13.3 days in a plane inclined 53 degrees from the equatorial. The most recent spacecraft tracking and telemetry data were collected on Jan. 15 by the 70 meter Deep Space Network station at Goldstone, California. Except for some science instrument issues described in previous reports, the spacecraft continues to be in an excellent state of health with all of its subsystems operating normally. Information on the present position of the Cassini spacecraft may be found on the "Present Position" page at: http://saturn.jpl.nasa.gov/mission/presentposition/.
Cassini's current orbital stability has not required the flight team to plan or execute any propulsive maneuvers since early December. The next orbit trim maneuver will take place at the end of this month. Work continued on the ten-week command sequences S78 and S79, which will go active on the spacecraft in March and June respectively. Planning also continued for Cassini's F-ring and Proximal Orbits phase, which will start in late 2016.
Wednesday, Jan. 9 (DOY 009)
The Cosmic Dust Analyzer (CDA) completed the first of three observations in the exogenous dust campaign, collecting data on particles coming from elsewhere in the solar system.
The Spacecraft Operations team sent a command to power off the Ultra Stable Oscillator. This frequency reference unit appeared to fail in December 2011; subsequent tests verified last July that it had suffered a hard failure. Turning it off saves about three watts of electrical power. Next, the flight team uplinked part one of the ten-week S77 command sequence using a 34 meter Australian Deep Space Network (DSN) station. After a round-trip light time of 2 hours 48 minutes, telemetry showed that all 8,490 commands were properly received and stored on board.
Thursday, Jan. 10 (DOY 010)
CDA began its second 37 hour exogenous dust observation, rolling the spacecraft about its Z-axis. The third began on Saturday and lasted 29 hours.
Nine years ago today, the Cassini imaging systems kicked off their approach science phase of the mission with imaging observations of the Saturnian system. Since then, just over 285,000 images have been acquired by the Imaging Science Subsystem (ISS).
Friday, Jan. 11 (DOY 011)
The DSN tracked Cassini, providing two-way digital and radiometric communications on four days this week, using stations in Australia and California.
Saturday, Jan. 12 (DOY 012)
Nearing the end of the S76 command sequence, the Imaging Science Subsystem (ISS), the Composite Infrared Spectrometer (CIRS) and the Visible and Infrared Mapping Spectrometer (VIMS) performed an observation in the Titan monitoring campaign from a distance of 2.5 million kilometers.
Cassini passed through apoapsis, having coasted 1.7 million kilometers from the planet and slowing to 10,894 kilometers per hour relative to Saturn. This marked the beginning of Cassini's 179th orbit.
Sunday, Jan. 13 (DOY 013)
The S77 sequence began executing with ISS, CIRS and VIMS jointly observing the thin, bright F ring for 16 hours.
Monday, Jan. 14 (DOY 014)
The radar instrument performed an engineering test of its diagnostic modes, then the Ultraviolet Imaging Spectrograph (UVIS), CIRS, and VIMS stared at Saturn's South Pole for 19 hours to study Saturn's aurora.
Eight years ago today, the European Space Agency's (ESA) battery-powered Huygens Probe entered Titan's atmosphere after a three-week, spin-stabilized cruise following release from the Cassini orbiter. After deploying two parachutes and shedding its back shell and heat shield, it deployed its instruments and drogue parachute. For the next two hours it descended through Titan's atmosphere returning data via the Cassini orbiter. Finally, the probe impacted the surface surviving the impact to return further data.
Tuesday Jan. 15 (DOY 015)
ISS performed an observation in the Satellite Orbit Campaign, looking at small satellites near Saturn. The Magnetometer then carried out an eight hour calibration while rotating the spacecraft about its X-axis.