ISS On-Orbit Status 31 May 2002

All ISS systems continue to function nominally, except as noted
previously or below.   It is Day 177 for the Expedition 4
crew (175 days onboard ISS).  The end of Increment 4 is near;
but not quite here:  STS-111/UF-2 was scrubbed last night
because of threatening thunderstorms near the pad. Tonight’s and
tomorrow’s opportunities were also waived because of weather outlook,
and the next attempt will be on Monday (6/3) evening.

Crew sleep cycle shift began last night, delaying bedtime by three
hours and setting wakeup at 5:00 am EDT this morning (instead of 2:00
am).  MCC-H and MCC-M (TsUP) medical personnel are in agreement
to hold the shift to three-hours for now until launch is a fact, then
implement the remaining portion of the sleep adjustment to
synchronize the day/night cycles of the ISS and Shuttle crews.

CDR Yuri Onufrienko prepared his Kentavr (Centaurus) equipment for
their return to Earth.  After the adjustment, Onufrienko tagged
up with a Kentavr specialist at TsUP. [The Russian Kentavr garment
is a protective anti-g suit to facilitate the return of a
long-duration crewmember into the Earth gravity.]

As generally every week on Saturday, the station residents
performed the 2-hour “uborka” (house cleaning), which includes wiping
surfaces with disinfectants and cleaning of all fan screens to avoid
temperature rises.  In the process, they gathered surface
samples for microbiological analysis from behind specific panels of
the FGB, particularly from cables, coils, vent inlets and TCS
(thermal control system) pipes.  The samples were collected in
test tubes, marked as to location and date, and packed for return on
STS-111.

MCC-H sent up thanks for yesterday’s highly informative videotape of
Carl Walz’s water transfer from the Lab condensate tank to a CWC
(collapsible water container) and its subsequent installation on the
Elektron CFU (condensate feed unit) for processing.

On ground request this morning, the crew performed a controlled
power-down of the VOA (volatile organics analyzer).

FE-1 Walz initiated the second round of recharging EMU spacesuit
batteries in the BSA (battery stowage assembly.  Batteries #3
and #4 were found to have terminated their charging several
ampere-hours short of what was anticipated to be a full charge
 (#3: 5 A-hr; #4: 8 A-hr).  Both batteries could still
adequately support an EVA; however, since Walz was also scheduled to
initiate a top-off charge on the middeck charger from PSA (power
supply assembly) utility outlet, he was asked to see if these
batteries will accept additional charge.

An update/correction of the Russian BINS strapdown inertial
navigation system was performed by CDR Onufrienko using GPS attitude
and state vector data.  The procedure went so well that TsUP
intends to use it in the future.  [BINS is a platform-less
(or "strap-down" in NASA parlance) inertial navigation
system, which uses a complex mathematical model of spatial
relationships (axes, rotations, angular velocities and accelerations)
instead of the gyro-stabilized and gimbaled platform of a more
conventional inertial navigation system.  To check and correct
the unavoidable drift of the internal reference orientation, the
standard procedure is to take optical sightings of reference stars;
attitude rates are obtained from the GIVUS high-accuracy state
sensors.]

Onufrienko was scheduled for a live televised PAO conference downlink
from the SM with a representative of the European "Astrium"
Company.

Carl Walz performed the daily routine tasks of Increment 4/8A payload
status checks and SOSH life support maintenance with ASU toilet
insert replacements, while Dan Bursch later power-cycled the IV-CPDS
(intravehicular charged particle directional spectrometer) for ground
commanding.

In preparation of the Shuttle docking, FE-2 Bursch worked on the
PMA-2 (pressurized mating adapter #2) in front of the Lab, initiating
its pressurization for seal leak checks.  Required equipment
included a 5-ft. VAJ (vacuum access jumper), a scopemeter for
pressure measurement, and an internal sampling adapter for the MPEV
(manual pressure equalization  valve).

After yesterday’s inspection of the BPS (biomass production system)
test facility, Bursch reported some kind of "black plastic
bits" floating in PGC3 (plant growth chamber #3) which currently
contains just a root tray with no plants.  POC (Payload
Operations Center) plans to turn on BPS lights and inspect the
chamber via video camera when Ku-band is available.

Moscow continues to be concerned about the thermal situation on the
Progress and Soyuz vehicles as well as the DC-1 docking compartment
docked to ISS during the current high solar Beta angle regime.
 Some parts of Progress are showing spurious temperatures above
the max limits. In particular, an attitude control thruster cover has
exceeded its max limit of 55 deg C by 10 degrees (however, if the
cover drive should fail to open, TsUP is confident that a jet firing
will push it open). The Soyuz, on the other hand, is docked at the
FGB nadir port in shadow and requires its heaters to keep its
internal temperature at a steady 16 deg C to prevent humidity
condensation.  The DC-1 docking module at the SM nadir port is
also being heated, after the crew had to dry off accumulating
condensation.  [To handle these temperature excursions during
high solar irradiation periods on Mir, the Russians used to flip Mir
through 180 deg every 12 hours.  On ISS, protecting both
Progress from heat and warming up Soyuz and DC-1 at the same time
during the infrequent very-high solar Beta regime probably requires
going to attitudes that are not (yet) certified. NASA has started
work this issue but requires more specifics on the Russian vehicles’
thermal characteristics, such as relaxation times, alpha/epsilon
(absorptivity over emissitivy) values, etc.]

The command for inhibiting control handover to the Russian MCS
(motion control system) in the event of a power failure of the USOS
Primary GNC (guidance, navigation & control computer) and Primary
C&C (command & control computer) during the Shuttle-docked
phase has been uplinked.  MCC-Moscow planned to test it today at
about 1:40 pm EDT.  The command will become active about 10
minutes before docking.

A conjunction with orbital debris was predicted yesterday for about
11:17 am EDT today.  No avoidance maneuver was required since
probability of collision went to zero during the night.
 [According to TsUP, it appears that Moscow received the
warning very late: at first a "yellow" warning at 9:15 pm
last night, followed by a "red" alert at 3:00 am this
morning.  Fifteen minutes later, the threat disappeared with a
"green" message, but TsUP would have had only about eight
hours time to prepare and uplink an appropriate maneuver data load
(the agreed-on time span is 16 hours before the conjunction).]

Onufrienko’s target zones for the Russian Diatomeya
ocean-observing program today were in the Pacific Ocean
(coral reefs and atolls in the waters of the Tuamotu archipelago
and Tyubuai archipelago), and Indian Ocean
(plankton-poor [i.e., extremely clear and thus dark blue] waters
of the central part of the subarctic eddy zone).

The U.S. CEO (crew earth observation) experiment had the following
targets today:  Malaysia (both the Malay Peninsula and
Sumatra were clear.  Of interest: documenting land clearing,
particularly around Singapore  at the tip of the Peninsula. This
pass was also excellent for taking detailed mapping photos of the
coral reefs between Sumatra and Malaysia. The seasonal rains are late
in coming and conditions have been unusually dry over Vietnam and
Cambodia; crew was to look left and record the condition of coastal
vegetation), Nyiragongo Volcano and Lake Kivu (Dynamic
Event: Nyiragongo volcano is active again and threatening the city of
Goma on the eastern shore of Lake Kivu. Clear weather should have
permitted the crew to document new lava flows — particularly on the
lakeward side of the mountain. Lake Victoria probably remained clear
as well, allowing the crew to record water levels; their observations
on the extent of water vegetation, which has been choking parts of
the lakeshore, were appreciated as well), Rift Triple
Junction, Ethiopia (as ISS traversed the Afar triangle, the
crew was asked to look right and sight down the SE-trending fault
escarpments that cut the dark, lava-covered land surface. Faults of
three orientations [NNW, SW, and NE] intersect in this tectonically
active region), and Panama Canal (Dynamic Event: It is
quite rare to have clear weather over the Canal Zone; the ITCZ has
shifted to the north at present. Detailed mapping views of resort and
other development on the north coast of Panama, are needed for
monitoring the health of wetlands in the region; photos of the
offshore islands are needed as well).
CEO images can be viewed at the website http://eol.jsc.nasa.gov

U.S. and Russian Segment Status (as of 2:36 pm
EDT):

Environmental Control and Life Support (ECLSS) and
Thermal Control (TCS):
Elektron O2 generator is powered On (32-amp mode)
Vozdukh CO2 scrubber is ON in MANUAL cycle mode #5 (vacuum pump
failed).  U.S. CDRA CO2 scrubber is Off.  BMP Harmful
Impurities unit: Absorbent bed #1 in Purify mode, bed #2 in Purify
mode.

SM Working Compartment:  Pressure (mmHg) — 760,
temperature (deg C) — 28.3, ppO2 (mmHg) — 149.1, ppCO2 (mmHg) —
2.6.
SM Transfer Compartment:  Pressure (mmHg) — 762,
temperature (deg C) — 21.5.
FGB Cabin:  Pressure (mmHg) — 756, temperature (deg C)
— 20.7.
Node:  Pressure (mmHg) — 750.25, temperature (deg C) —
24.0 (shell); ppO2 (mmHg) — n/a; ppCO2 (mmHg) — n/a.
U.S. Lab:  Pressure (mmHg) — 753.60, temperature (deg C)
— 25.2, ppO2 (mmHg) — n/a; ppCO2 (mmHg) — n/a;
Joint Airlock (Equip. Lock):  Pressure (mmHg) — 753.60,
temperature (deg C) — 23.7; shell heater temp (deg C) — 23.6, ppO2
(mmHg) — n/a; ppCO2 (mmHg) — n/a.
PMA-1:  Shell heater temp (deg C) — 24.0
PMA-2:  Shell heater temp (deg C) — 17.4

(Note: Partial pressures ppO2 and ppCO2 in U.S. segment [USOS] not
available because MCA [major constituent analyzer] is failed and in
Extended Life mode [= a state that preserves mass spectrometer
vacuum but produces no pp data]). MSA (mass spectrometer assembly)
and VGA (verification gas assembly) have been removed for return to
Earth.

Electrical Power Systems (EPS):
Beta Gimbal Assembly (BGA) 2B in Autotrack mode, BGA 4B in
Autotrack mode.
SM batteries: data not available
FGB: Battery #3 is offline (ROM mode). All other batteries (5) are in
“partial charge” mode.
Plasma Contactor Unit PCU-1 in Standby mode; PCU-2 in Standby
mode.

Thermal Control Systems:
Air conditioner SKV-1 is Off. SKV-2 is On.

Command & Data Handling Systems:
C&C-3 MDM is prime, C&C-2 is back-up, and C&C-1
is in standby.
GNC-1 MDM is prime; GNC-2 is Backup.
LA-1, LA-2 and LA-3 MDMs are all operating.
PL-1 MDM is operational; PL-2 MDM on Standby.
APS-1 (automated payload switch #1) and APS-2 are both On.
SM Terminal Computer (TVM): 2 redundant lanes (of 3) operational.
SM Central Computer (TsVM): 2 redundant lanes (of 3) operational.

Communications Systems:
All Russian communications & tracking systems are
nominal.
S-band is operating nominally.
Ku-band is operating nominally.
Audio subsystem operating nominally.
Video subsystem operating nominally.
MCOR (medium-rate communications outage recorder) is operating
nominally.

Robotics:
SSRMS/Canadarm2 at Progress viewing position, with Keep Alive
power on both strings.
RWS (robotics workstations) are Off.
SSRMS Prime string Wrist Roll (WR) joint to be replaced on UF-2.

ISS Orbit (as of this morning, 9:29 am EDT [=
epoch]):
Mean altitude — 387.1 km
Apogee — 391.7 km
Perigee — 382.6 km
Period — 92.3 min.
Inclination (to Equator) — 51.63 deg
Eccentricity — 0.0006675
Orbits per 24-hr. day — 15.60
Altitude decrease — 150 m (mean) in last 24 hours
Revolutions since FGB/Zarya launch (Nov. ’98) — 20126
Current Flight Attitude — XPOP (x-axis perpendicular to orbit
plane = “sun-fixed” [yaw: ~180 deg, pitch: -5.6 deg., roll: 0
deg]).

For more on ISS orbit and naked-eye visibility dates/times, see
http://www.hq.nasa.gov/osf/station/viewing/issvis.html