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Cassini Significant Events 02/10/10 – 02/16/10

The most recent spacecraft telemetry was acquired on Feb. 16 from the Deep Space Network tracking complex at Madrid, Spain. The Cassini spacecraft is in an excellent state of health and all subsystems are operating normally. 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/.

Wednesday, Feb. 10 (DOY 041)

Featuring Cassini and several other missions, an Outer Planets Display titled "From Galileo to the Outer Planets, 400 Years of Discovery," was scheduled to debut at the Rayburn Congressional Office building on Feb 10th in Washington D.C. Unfortunately, the city was closed due to snow, so the event did not occur. Look for future information on when the display will be rescheduled.

Galileo was born 446 years ago this week, and 400 years ago this year he first aimed his modest telescope at Saturn, and was surprised to see what appeared to be three planets close together. Two years later, in 1612, the two smaller planets had vanished from his view. You can read about the history of Saturn observation here on the Cassini Saturn Observation campaign page:

The Cassini spacecraft's Twitter persona, Cassini Saturn (http://twitter.com/CassiniSaturn), is one of Twitter's top "Sources in Science" recommendations.

Thursday, Feb. 11 (DOY 042)

Today, the Lunar Reconnaissance Orbiter Project requested DSN coverage that impacted Cassini's scheduled tracks. The Cassini DSS-54 track was ended at 0545 instead of 0735, and DSS-63 agreed to extend parallel coverage to 0735. Navigation was notified that 2-way tracking data would be changed to 3-way. No science data was lost as a result of the change.

Sun Sensor Assembly (SSA) B was powered on today for the dust hazard crossing on Feb. 13. The sensor will be powered off via real time command on Feb. 14.

Friday, Feb. 12 (DOY 043)

This week the Ultraviolet Imaging Spectrograph (UVIS) performed a mosaic scan of Saturn's magnetosphere, mapped volatiles in the immediate neighborhood of Enceladus to test for connection of volatile changes to plume eruptions, and performed several slow scans across Saturn's visible hemisphere to form spectral images. The Composite Infrared Spectrometer (CIRS) used FP1 and FP3 to map Mimas during the daytime, measured oxygen compounds in Saturn's stratosphere, and obtained stratospheric thermal structure by means of limb sounding in the mid-infrared. The Cassini Plasma Spectrometer (CAPS) performed a Magnetospheric and Plasma Science (MAPS) survey. Imaging Science (ISS) observed phase function of plumes on Enceladus, an ingress solar eclipse, Mimas, Iapetus, Calypso, Titan's clouds, and the transit of Epimetheus across Janus. The Visual and Infrared Mapping Spectrometer (VIMS) took data for a global dynamics mosaic of Saturn's equator. RADAR performed scatterometry and radiometry on Saturn's satellite Mimas.

Saturday, Feb. 13 (DOY 044)

Non-targeted flybys of Calypso, Epimetheus, Janus, Mimas, and Tethys occurred today. Tomorrow a non-targeted flyby of Titan will occur.

Monday, Feb. 15 (DOY 046):

The main engine cover was opened today, completing the 57th in-flight cycle for the cover.

In a nod to Galileo's 446th birthday and 400 years since he first looked at Saturn through a telescope, a Cassini image of Saturn's "disappearing" rings was Astronomy Picture of the Day today. Check it out at:

At the request of the Deep Space Network, Uplink Operations sent real-time commands to the spacecraft to turn on the Radio Science Ka-Band for testing on DOY 050 and 056. In addition, a CAPS patch for testing of the Ion Beam Spectrometer was uplinked. The test will execute on Feb. 20.

Tuesday, Feb. 16 (DOY 047)

On Feb. 13, Cassini acquired close-up images of Mimas, the moon likened to the Death Star from ³Star Wars² and the enormous crater scarring its surface. The flyby also yielded good data on the moon¹s thermal signature and surface composition. The images, which have the highest resolution so far, also show jumbled terrain inside the giant Herschel Crater, and many craters within the crater. These features hint at a long history, which scientists will be working diligently to analyze. The Mimas flyby involved some additional sequencing effort because the spacecraft had to pass through a dusty region to get there. Mission managers planned for the spacecraft to lead with the high-gain antenna to provide a protective shield. At closest approach, Cassini flew about 9,500 kilometers above the moon. For the full text of this feature link to:

The Cassini spacecraft captured a "mutual event" between Titan and Mimas in front of a backdrop of the planet's rings. An image was snapped shortly before Saturn's largest moon passed in front of and occulted the small moon, as seen from the spacecraft. For the full text and image link to: