ISS On-Orbit Status 19 Apr 2002
All ISS systems continue to function nominally, except as noted
previously or below.
Today was a relatively light day for the crew.
Early in the morning, at 1:20 am EDT, attitude control was handed
over to the Russian MCS (motion control system) to maneuver the
station to reboost attitude. Progress 7P at the SM aft port
then performed a single reboost burn of 118 sec duration, generating
a delta-V of 0.6 m/s and lifting the station by about 1 km in mean
altitude. [Since the burn was at apogee, the perigee
(low point of elliptical orbit) got most of the increase. This is the
preferred mode for single burn reboosts since it results in the most
drag reduction as it reduces air drag where it is highest.]
Main onboard activity today was the installation of two jumper
cables in the TCS (thermal control system) in the U.S. segment (USOS)
by FE-1 Carl Walz and FE-2 Dan Bursch, followed by a test of the TCS.
This procedure was necessary to protect for the case of a leak
in the unmanned vehicle during tomorrow’s Soyuz relocation. The
TCS jumper ?de-install? is planned to take place next Thursday.
However, the LTL (low temperature loop) temperature was
elevated by the ground while the jumpers were installed, and
therefore the de-install is listed on the "job jar" task
list to start on Sunday, 4/21. If the Lab gets too warm, the
crew is free to reconfigure the TCS jumpers at their convenience.
Detailed data on the Russian Uragan and Diatomeya experiments were
uplinked to CDR Yuri Onufrienko, for the next several days starting
on Sunday. [The Russian GFI-8 Uragan (?hurricane?) earth viewing
program uses a Sony DCS460 digital still camera, LIV video camera
equipment and recorded commentary by Yuri for selected observations
of natural and man-made disaster areas on Earth, such as hurricanes
and earthquakes. Diatomeya is the photographic and video
observation of the world?s oceans to look for areas of
bioproductivity (algae ?blooms?, diatoms, etc.).]
MCOR (medium-rate communications outage recorder) was
power-cycled by the ground (i.e., turned on-off) twice but continues
to be non-operational. The crew noted that MCOR was beeping
once per sec until the first power cycle and has been beeping at a
much slower rate of once per 7.5 minutes until it started beeping at
once per sec again. These signatures provide valuable
information to the ground for fixing the system.
Troubleshooting is continuing accordingly, and future steps
will include power cycling MCOR again.
The BPS (biomass production system) activity recorded by Dan Bursch
on video recorder VTR1 was successfully downlinked by the ground. The
tape was then rewound and it can be used again for recording. Both
VTR1 and VTR2 are ready to support Soyuz redocking tomorrow
morning.
FE-2 Bursch completed the daily routine payload status checks in the
Lab, while FE-1 Walz was scheduled to power-cycle the IV-CPDS
(intravehicular charged-particle spectrometer).
Space Shuttle STS-110/Atlantis landed successfully at KSC at 12:27 pm
EDT in bright sunshine.
