Status Report

NASA Space Station On-Orbit Status 10 Dec 2003

By SpaceRef Editor
December 10, 2003
Filed under , , ,
NASA Space Station On-Orbit Status 10 Dec 2003
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All ISS systems continue to function nominally, except as noted previously or below.

The crew received kudos this morning for their excellent work yesterday on the first half of the TVIS treadmill IFM (in-flight maintenance). Today’s 4.5-hr. job (still underway at this writing) was to replace the frayed wire rope loops, put everything back together again and reinstall the TVIS in the Service Module (SM) pit for operation (outcome to be reported tomorrow). [After removing the big machine from the pit and opening the gyro housing, some fine black powder residue was discovered (perhaps lubricant from broken bearing seals?), the top bearing of the horizontal flywheel was found to have significant resistance when spun by hand, and the bottom bearing appeared a little stiff. Downlinked photography provides excellent detailed views, and a number of clarifying questions were uplinked before today’s reassembly activities. Once back in operation, the plan is to use the treadmill without its roll-stabilizing gyrodyne, but with yaw and pitch stabilizers engaged.]

FE Alexander Kaleri continued the latest maintenance round on the Russian segment (RS) ventilation system, today cleaning the Group A fans and grilles in the SM (last time done: 11/5).

Sasha terminated the bake-out cycle on the BMP micropurification system’s channel 2, moding the channel back to Purify. This restored both filter beds of the trace contaminants removal system to Purify mode. [The regeneration of the air purifier filter beds is repeated every 20 days. Each bakeout to space vacuum takes about 24 hours.]

CDR Michael Foale set up and reviewed the DOUG (dynamic operations ubiquitous graphics) software version for tomorrow’s 2.5 hours of SSRMS robotarm proficiency exercise. [DOUG is a periodically updated software program on the MSS (mobile service system) workstation laptops that provides a birdseye-view graphical image of the external station configuration and the SSRMS arm, showing its real-time location and configuration via computer graphics during its operation. Tomorrow’s robotics ops, for honing crew proficiency, will consist of a visual inspection of the SM portside to check for any indications of the cause of the noise heard on 11/26. The survey will also cover the P6 truss’ 4-bar linkage shoulder bolts to determine if the bolts have backed out, and it will additionally provide general views of the zenith (top) side of the ISS, including the FGB and the Z1 and P6 truss segments, to look for any anomalies.]

Both crewmembers completed their daily 2.5-h program of physical (aerobic & anaerobic) exercise, on CEVIS bike, RED expander and on the Russian VELO cycle ergometer with load trainer. The CDR also conducted the periodic (every other week) inspection of the RED and monthly RED bolt tightening (as required).

The FE prepared the daily IMS delta file for automatic export/import to update the database performed the daily routine maintenance of the SOZh life support system (including ASU toilet facilities), while Mike completed the regular routine status checkup of the autonomous Increment 8 Lab payloads.

The crew continues to support the Renal Stone prevention experiment by taking the test medication (either potassium citrate or placebo tablets) at dinnertime until the next sample collection phase.

Yesterday evening the Elektron oxygen generator in the SM sustained a failure of its primary pump, followed 26 min. later by failure of the backup pump. The O2 generator was successfully restarted this morning at 2:14am EST and is running nominally. [An Elektron shutdown has no immediate impact since there are about 12 days’ worth of O2 stored in the Progress 12P resupply tank.]

CMG Watch:Early in the morning yesterday, a slight rise in spin motor current was observed on CMG-3 (control moment gyroscope #3). The increase (0.013 amp/hr) lasted for about five hours, after which it leveled out. There is no impact and the system continues to perform nominally. [Careful observation and analysis of available vibration, temperature and current data continue. The observed current signature is being questioned as (a) a potential indication of prolonged degradation of the CMG, (b) an inherent characteristic of the lubricant used in the spin motor bearings, or (c) perhaps a “health jump” or improvement of CMG performance.]

Some Background on CMGs: The four U.S. CMGs in the Z1 truss (one failed gyro, #1, will be replaced on the next Shuttle visit) are massive (~300 kg each) flywheels suspended in concentric gimbal rings such that each rotor has two degrees-of-freedom in its motion. Electric motors on the gimbals reposition the rotor spin axis with reference to the station, as computed by the GNC (guidance, navigation & control) software, to generate torques such that attitude disturbances of the station are countered. This nonpropulsive attitude control allows high-quality microgravity activities for extended periods and conserves propellant supplies. Although the CMGs have no mechanical hard stops in their gimbaled motion (as our Skylab CMGs had), they can reach a point where, due to growth of stored momentum, they are no longer capable to produce enough torque in a particular direction to counter disturbance torques in that direction. Before this situation occurs, at a settable threshold (e.g., the 80% point), the GNC computers automatically request a “momentum desaturation” by having the Russian reaction control system (RCS) thrusters fire in a specific manner, thereby providing a firm “backstop” against which the GNC software and the electric gimbal motors can reposition the CMG gimbals to a more optimal position with better torquing “leverage”. While the CMGs, besides holding attitude stable, are normally also used for ISS maneuvering through small angular rotations (less than 15 deg), in the current mode, valid until 1/15/04, all rotational maneuvers are relegated to the RCS thrusters. The CMGs are only doing their regular “momentum management” (attitude holding), which still requires Thruster Assist (TA) for some desaturations, in this case commanded “manually” from the ground instead of fully automatic.

Launch dates for next year’s Russian vehicles were approved by Moscow as follows:

  • Progress 13P (M1-260) — 1/29/04, preceded by a phasing reboost on 1/8/04;
  • Soyuz 8S (TMA-4) — 4/19, preceded by reboosts on 3/3 & 3/31;
  • Progress 14P (M-249) — 5/19;
  • Progress 15P (M-350) — 7/28;
  • Soyuz 9S (TMA-5) — 10/9;
  • Progress 16P — 11/24.

Today’s CEO targets, in the current LVLH attitude no longer limited by flight rule constraints on the use of the Lab nadir/science window, were S Chad Swamplands (sun glint opportunity right of track: mapping strip for ~1.5 minutes was requested at nadir and just right of track to help map margins of these features which change through time. Modern margins are of interest to ecologists, ancient margins to geologists since they indicate on-continent sedimentation of vast proportions. Handheld imagery is ideal for understanding which rivers have been responsible for this sedimentation),Toshka Lakes, Egypt (nadir and right of track. This sun glint opportunity is ideal for revealing the small connector waterways between the five new Toshka lakes, four of which apparently were unplanned),W Africa biomass burning(Dynamic event: Looking left and right during this cloud free spell for the continuing major burning event),Glacial features, W Libya(looking nadir and a touch right. Suggested was a mapping swath for 60 seconds to capture sub-ice river features of great interest: a continental-scale ice sheet developed when North Africa lay astride the South Pole [~450 million years ago]. Meltwater under the ice created wide riverbeds that were buried and subsequently re-exposed by erosion. The beds can be seen from space as sinuous features. The special interest of these features is that are known to hold fluids in some places. A fuller map of their distribution is in preparation with collaborating scientists),Eastern Mediterranean Haze(looking left for probable smog accumulation in the Po River Valley, Italy’s industrial heartland, as a high pressure system builds in. Also, looking left for the first clear panoramas of the Alps under snow),Berlin, Germany(looking a touch left for this major, wooded city. Two images should be sufficient to capture the whole urban region for the cities study), andSE Australia floods(Dynamic event: Major floods in SE Australia have devastated wide areas. Looking left towards the coast to document any sediment-laden river water entering the sea).

CEO images can be viewed at the websites.

See also the website “Space Station Challenge” at

U.S. and Russian Segment Status (as of 1:20pm EST).

Environmental Control and Life Support (ECLSS) and Thermal Control (TCS):

  • Elektron O2 generator is powered On, 18A. Vozdukh CO2 scrubber is On (in Manual Mode 5/3). U.S. CDRA CO2 scrubber is on Standby (ready in dual-bed mode). TCCS (trace contaminant control subsystem) is operating. MCA (major constituents analyzer) is off (in Life Extending Mode). BMP Harmful Impurities unit: absorbent bed #1 in Purify mode, bed #2 in Purify mode. RS air conditioner SKV-1 is On; SKV-2 is Off.
  • SM Working Compartment: Pressure (mmHg) — 742; temperature (deg C) — 26.3; ppO2 (mmHg) — 151.7; ppCO2 (mmHg) — 4.7.
  • SM Transfer Compartment: Pressure (mmHg) — 761; temperature (deg C) — 20.0.
  • FGB Cabin: Pressure (mmHg) — 756; temperature (deg C) — 21.7.
  • Node: Pressure (mmHg) — 750.25; temperature (deg C) — 23.3 (shell); ppO2 (mmHg) — n/a; ppCO2 (mmHg) — n/a.
  • U.S. Lab: Pressure (mmHg) — 752.39; temperature (deg C) — 24.7; ppO2 (mmHg) — n/a; ppCO2 (mmHg) — n/a.
  • Joint Airlock (Equip. Lock): Pressure (mmHg) — 752.59; temperature (deg C) — 26.8; shell heater temp (deg C) — 24.7, ppO2 (mmHg) — n/a; ppCO2 (mmHg) — n/a.
  • PMA-1: Shell heater temp (deg C) — 22.2
  • PMA-2: Shell heater temp (deg C) — 12.9

(n/a = data not available)

Electrical Power Systems (EPS):

  • Both P6 channels fully operational. BGA (beta gimbal assembly) 2B and 4B both in Directed Position (non-suntracking).
  • SM batteries: Battery #8, formerly known as #7, is still disconnected in slot #8 for troubleshooting, off-line; all other batteries (7) are in “Partial Charge” mode.
  • FGB batteries: Battery #5 is off (capacity restoration mode, ROM); battery #4 is in “Cycle Mode”; all other batteries (4) are in “Partial Charge” mode.
  • Plasma Contactor Unit PCU-1 in Standby mode; PCU-2 in Standby mode.

Command & Data Handling Systems:

  • C&C-1 MDM is prime, C&C-2 is back-up, and C&C-3 is in standby.
  • GNC-1 MDM is prime; GNC-2 is Backup.
  • INT-2 is operating; INT-1 is Off.
  • EXT-2 is On (primary), EXT-1 is Off (both now upgraded to R3).
  • LA-1, LA-2 and LA-3 MDMs are all operating.
  • PL-1 MDM is Off; PL-2 MDM is Operational.
  • APS-1 (automated payload switch #1) and APS-2 are both On.
  • SM Terminal Computer (TVM): 2 redundant lanes (of 3) operational (string 1 dropped out 11/22).
  • SM Central Computer (TsVM): 2 redundant lanes (of 3) operational (string #3 dropped out 10/22).

Propulsion System:

  • Total propellant load available:3703 kg (8164 lb) as of 12/4/03[SM(755) + FGB(2596) + Progress M(352) + Progress M-1(0)]. (Capability: SM — 860 kg; FGB — 6120 kg).

Attitude Control Systems:

  • 3 CMGs on-line (CMG-1 failed).
  • State vector source — U.S. SIGI-1 (GPS)
  • Attitude source — U.S. SIGI-1 (GPS)
  • Angular rate source — RGA-1

Flight Attitude:

  • LVLH YVV (local vertical/local horizontal = “earth-fixed”: z-axis in local vertical, y-axis in velocity vector [yaw: 90.2 deg, pitch: -10.8 deg, roll: -3 deg]), with CMG/TA (thruster assist) Momentum Management.

Communications & Tracking Systems:

  • FGB MDM-1 is powered Off; FGB MDM-2 is operational.
  • All other Russian communications & tracking systems are nominal.
  • S-band is operating nominally (on string 2).
  • Ku-band is operating nominally.
  • Audio subsystem is operating nominally (IAC-1 is prime, IAC-2 is off).
  • Video subsystem operating nominally.
  • HCOR (high-rate communications outage recorder) is operating nominally.

Robotics:

  • SSRMS/Canadarm2 based at MBS PDGF #2/LEE A, with Keep Alive (KA) power on both strings.
  • MBS: KA power on both strings.
  • MT: latched and mated at WS4.
  • POA: KA power on both strings.
  • RWS (robotics workstations): Lab RWS is On (DCP connected); Cupola RWS is Off.

ISS Orbit (as of this morning, 6:25am EST [= epoch]):

  • Mean altitude — 371.8 km
  • Apogee — 375.9 km
  • Perigee — 367.8 km
  • Period — 92.0 min.
  • Inclination (to Equator) — 51.63 deg
  • Eccentricity — 0.0006031
  • Orbits per 24-hr. day — 15.65
  • Mean altitude loss in last 24 hours — 45 m
  • Revolutions since FGB/Zarya launch (Nov. ’98) — 28856
  • For more on ISS orbit and worldwide naked-eye visibility dates/times, see
  • http://www.hq.nasa.gov/osf/station/viewing/issvis.html

SpaceRef staff editor.