NASA Cassini Significant Events 02/29/2012 – 03/06/2012

The most recent spacecraft tracking and telemetry data were collected March 7 using the Deep Space Network’s 34 meter Beam-Waveguide Station 25 at Goldstone in the California desert. The Cassini spacecraft is in an excellent state of health. All subsystems are operating normally except for the issues being worked with the Cassini Plasma Spectrometer and the Ultrastable Oscillator. Information on the present position and speed of the Cassini spacecraft may be found on the “Present Position” page at: http://saturn.jpl.nasa.gov/mission/presentposition/ .

Twice this week, Cassini rotated to point its Imaging Science Subsystem (ISS), Composite Infrared Spectrometer (CIRS), and Visual and Infrared Mapping Spectrometer (VIMS) telescopes toward Saturn’s largest satellite for more Titan Monitoring Campaign observations. At other times, the instruments were pointed toward Saturn for the Ultraviolet Imaging Spectrograph (UVIS) and ISS to measure and monitor the planet’s aurorae.

Wednesday, Feb. 29 (DOY 060)

UVIS surveyed the abundance of interplanetary hydrogen by remote sensing from 2.4 million kilometers above Saturn.

Commands were sent to the spacecraft to do a “live” update of the running Inertial Vector Propagator. This ensures best instrument pointing for an observation of Saturn’s large icy satellite Rhea next week.

Thursday, March 1 (DOY 061)

Apoapsis passage early today (Universal Time) marked the start of Cassini’s 162nd orbit of Saturn. Having slowed to 5,463 kilometers per hour relative to the planet, the spacecraft begins its nine-day plunge, still in the equatorial plane, gathering speed on its arc back toward Saturn.

Friday, March 2 (DOY 062)

The Cosmic Dust Analyzer made direct measurements of interstellar dust particles as they interacted with the instrument. ISS carried out an 18-hour observation of the outer irregular satellite Thrymr to measure the rotational phase curve.

The feature “Cassini Detects Hint of Fresh Air at Dione” was posted online: http://saturn.jpl.nasa.gov/news/cassinifeatures/feature20120302/

The Attitude and Articulation Control Subsystem executed a Reaction Wheel Y-Bias maneuver to adjust wheel speeds while Cassini was off Earth point.

Saturday, March 3 (DOY 063)

The spacecraft rolled about its Z axis to perform a Magnetometer (MAG) calibration. There is an animation of a typical MAG roll here: http://1.usa.gov/xlYR7U .

Sunday, March 4 (DOY 064)

Still some 2.2 million kilometers from Saturn, UVIS again surveyed the hydrogen in interplanetary space.

Cassini rolled for several hours to perform another MAG calibration, this time keeping its High-Gain Antenna dish trained on Earth to maintain two-way communications.

Commands for Orbit Trim Maneuver 312 were uplinked to the spacecraft using Deep Space Station 14 at Goldstone, California. The maneuver will execute March 9, but was uplinked early as a precaution; there would be a heavy delta-V cost if it were delayed.

Monday, March 5 (DOY 065)

Commands for the Cassini Plasma Spectrometer (CAPS) are still being issued from the S72 background sequence that is running, but since the instrument is turned off, there are no results. Pending the outcome of a review next week, it may be possible to turn CAPS back on before the sequence ends.

Tuesday, March 6 (DOY 066)

Cassini passed 717,800 kilometers from Titan on its way inbound toward Saturn; this occurred during a Deep Space Network tracking pass.

An “Insider’s Cassini” article, “How to Plan Your Flyby” was published here: http://saturn.jpl.nasa.gov/news/cassiniinsider/insider20120306/ .