Status Report

NASA Cassini Significant Events for 08/20/03 – 08/27/03

By SpaceRef Editor
August 30, 2003
Filed under , ,
NASA Cassini Significant Events for 08/20/03 – 08/27/03

The most recent spacecraft telemetry was acquired from the Goldstone
tracking station on Wednesday, August 27. The Cassini spacecraft is in
an excellent state of health and is operating normally. Information on
the present position and speed of the Cassini spacecraft may be found
on the "Present Position" web page located at .

On-board activities this week included regularly scheduled Backup ALF
Injection Loader maintenance, and clearing of the ACS high water marks.
Instrument activities included a Cassini Plasma Spectrometer flight
software checkout, a Composite Infrared Spectrometer remote sensing
pallet heater test, a Magnetometer Subsystem SSR library load test, a
Probe mute test, and several Radio and Plasma Wave Science High
Frequency Receiver calibrations.

August 18 marked the 4-year anniversary of Cassini’s Earth flyby. Earth
was the third in a four-planet gravity assist trajectory – Venus Venus
Earth Jupiter – that has been utilized by the spacecraft to enable it to
reach Saturn in July of 2004.

A kick-off meeting was held for the C40 cruise sequence. Stripped
spacecraft activity sequence files to be used in this process were
released to the teams. C40 is the last sequence in the Cassini Space
Science Subphase. The next subphase, Approach Science, contains C42,
C43, and C44. These will be followed by the first tour sequences
beginning with S1.

Last week’s Live Update Verification and Validation (V&V) activity
concluded successfully. Products from that exercise are currently being
run in Cassini’s Integrated Test Laboratory. This facility allows
simulation of exact conditions on board the spacecraft, and enables
commands to be tested without any operational risk.

Uplink Verification and Validation (V&V) is now concluded. A wrap up
review was held covering action items and lessons learned from the
Science Operations Plan (SOP) Update, Science and Sequence Update, and
Live Update V&V activities.

Products were delivered for official input port #1 for Science
Operations Plan implementation of tour sequences S01, S02, S03, and
S04. The input files for S01 an S02 are currently being merged and will
be delivered to ACS for end-to-end pointing analysis. ACS analysis is
complete for files from S03 and S04.

Last week it was incorrectly reported that RPWS had produced a pre-peer
review volume of archive data, and a peer review volume of Gravitational
Wave Experiment 1 data for Planetary Data System (PDS) review. The
correct statement is that RPWS produced a pre-peer review volume of
archive data for the PDS review, and the Radio Science Subsystem (RSS)
produced a peer review volume of Gravitational Wave Experiment 1 data
for PDS review. Apologies to these instrument teams for last week’s
incorrect report.

As a result of their participation in the recent Saturn Orbit Insertion
(SOI) demonstration, the RSS group has submitted a report to the Cassini
Program on support of real-time visibility into events that will occur
during SOI.

The Navigation Team has released an update to the Cassini Navigation
Plan. This version contains the navigation strategy and predictions for
approach, SOI, tour, and Huygens probe delivery.

Cassini Outreach gave a presentation on the Cassini mission to 40
educators from Astrocamp.

In early 2005, the European Space Agency’s (ESA) Huygens probe will
descend through the cloak of gases surrounding Titan, Saturn’s largest
and most mysterious moon. An Italian-led team of European scientists and
engineers has ingeniously tackled the challenges of testing the
reliability, behavior, and response of some of the probe’s instruments
in actual operation — not simulations.

Scientists gathered at the Italian Space Agency’s Trapani balloon-launch
facility in Sicily to launch a 500-kilogram gondola carrying the mock-up
Huygens space probe. A helium balloon that fully inflated to a diameter
of 100 meters at its maximum altitude raised the gondola to a height of
33 kilometers, at which point a release mechanism opened and dropped the
probe. The on-board parachute deployed to slow the probe’s fall from 40
meters per second to just 4 meters per second. At that speed, the probe
floated gently back to Earth, taking about 30 minutes to complete its
journey beneath the ten-meter-wide parachute. This parachute was
designed to provide a fall speed very close to the one expected at
Titan. For more information link to ESA News

Cassini is a cooperative project of NASA, the European Space Agency and
the Italian Space Agency. The Jet Propulsion Laboratory, a division of
the California Institute of Technology in Pasadena, Calif., manages the
Cassini mission for NASA’s Office of Space Science, Washington, D.C.

SpaceRef staff editor.