Status Report

NASA Space Station On-Orbit Status 30 May 2003

By SpaceRef Editor
May 30, 2003
Filed under , ,
NASA Space Station On-Orbit Status 30 May 2003
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All ISS systems continue to function nominally, except as noted previously or below.

The crew’s day today was largely dominated by the yearly TVIS (treadmill with vibration isolation and stabilization) maintenance.  A healthy chunk of 6.5 hrs had been reserved on the timeline for the task, which involved a close inspection, several replacements of worn-out parts and subsequent activation and checkout, particularly of the vibration isolation system (VIS), including a power draw test and actual exercise run.  Imagery of the activities was obtained with a video camcorder set up beforehand and a digital still camera.   [Starting at 4:00am EDT, Edward Lu and Yuri Malenchenko were scheduled to remove TVIS from the Service Module (SM) “pit”, replace the transfer (gearbox) case and flywheel case with new ones brought up by Soyuz 6S with Expedition 7, reposition the forward gyro bracket lip top wire plate in its proper orientation and replace IRBA (isolation restoration bungee assembly) bungees.  Their tasks also included inspection of the SM pit subfloor for any debris or material, checking gyroscope positioning, verification of torque values on accessible fasteners for SPDs (subject positioning devices), aft stabilizers, VIS, and electronics box, identification of stabilizer locations, and removal of an old battery from a spare electronics box in stowage.]

As part of regular daily tasks, CDR Yuri Malenchenko inspected the BRPK-1 air/liquid condensate separator of the SM’s SRVK water processing system and conducted his regular daily monitoring/servicing of the BIO-5 Rasteniya-2 zero-G plant growth experiment, checking water level in the Lada-2 greenhouse water container and the seed status.

Meanwhile, FE/SO Ed Lu did the regular status checkup of the autonomous Lab payload (PCG-STES010, SAMS, MAMS).

To improve cabin ppCO2 analyses in the Russian segment (RS), Malenchenko performed a 45-min. recalibration of the SM’s gas analyzer (IK0501) for CO2 readings.   [IK0501 analyzes the air flow pumped through it for humidity (H2O), oxygen (O2), carbon dioxide (CO2) and hydrogen (H2), and converts its measurements into partial pressure values going to a monitoring laptop and, if they exceed limit values, to the caution and warning panel (PSS).]

After their regular daily physical exercise, the crew also had their weekly teleconference with the ISS Flight Director at MCC-H.

Ed and Yuri received warm kudos for yesterday’s successful Educational Payload Operations (EPO) session, which demonstrated zero-G flight of paper airplanes and a model of the Wright Flyer.  Next EPO will be the demo of a Hawaiian flute called a Pu’ili.

Conjunction update:  The Progress maneuver burn to remove the risk of collision with an orbital object was successfully performed on schedule at 12:50pm EDT over Russian ground sites.  [Collision probability with the Italian Megsat 0, launched in April 1999 on a Russian Kosmos-3M rocket, at a TCA (time of closest approach) of 4:55pm EDT, remained within the “Red” zone (greater than 1 in 10,000) throughout the night and all morning.  The burn, planned to last 7 min 27sec, was performed on the four manifold-2 thrusters of Progress 10P, using props (N2O4, nitrogen tetroxide & UDMH, unsymmetrical dimethyl hydrazine)  from the cargo ship’s refueling tanks.  Required delta-V was ~1 m/s, resulting in an altitude increase of 1.7 km.  This moved the object out of the Red and Yellow zones (Yellow = greater than 1 in 100,000, but smaller than 1 in 10,000) and resulted in safe separation (predicted: 2 km radial, 25 km along-track, 25 km cross-track).  The maneuver took care of all three Megsat conjunctions and also of another upcoming conjunction with a rocket booster.  For the burn, the ISS maneuvered to the required minimum propellant attitude (LVLH, yaw/pitch/roll 0/0/0) at 10:20am and returned to XPOP at 1:03pm.  Orbital drag uncertainties involved in the predictive calculations were increased by solar flare activity; see following item.]

Due to multiple violent solar flares (Class X) in the last two days, a large coronal mass ejection (CME) passed the Earth late yesterday, resulting in geomagnetic storm conditions.  Arrival of a second CME is projected for today between 5:00pm and 2:00pm tomorrow (most likely: 3:00am), generating another geomagnetic storm with an estimated shock strength of 4 on a scale of 0 to 9 (strongest).  The crew was notified to watch for auroras during their orbital night, near New Zealand, the southern parts of Australia, and North America.   [CMEs are violent discharges of material from the Sun’s outer atmosphere.  The ejected material can travel at speeds of up to a million miles per hour.  When this flow of charged particles and embedded magnetic field collides with Earth, it can dramatically disrupt Earth’s geomagnetic field and ionosphere. The ensuing geomagnetic storms can result in disrupted communication networks, errors in navigation systems, satellite failures, electricity blackouts, radiation hazards to astronauts, disruption of flow meters in oil pipelines, aggravation to geophysical exploration for natural resources, etc.  The impact shock also heats the ionosphere, causing increases in ionospheric density and drag force on orbiting vehicles.  The current storms are not seen to be of a magnitude that would cause any significant elevation in intravehicular crew exposures, i.e., there is no crew health risk.]

Today’s CEO targets, limited in the current XPOP attitude by flight rule constraints on the use of the Lab nadir/science window, also excluding any night target viewing, were Industrialized SE Africa (good pass for seeing air quality at three topographic levels: looking right for the coastal plain [0-3000 feet altitude]; looking oblique left for the plateau [4-6000 feet], where haze accumulations are generally greatest; looking left closer to track for the Lesotho highlands [7-10,000 feet] for the clearest air [usually above the inversion layer that holds aerosols near the plateau surface, especially in this winter season]), Taiwan aerosols (ideal pass over the strait between Taiwan and the mainland to photograph industrial haze on the western, populated side of the island), Beijing, China (good pass just to the north of the metropolis. Looking right for the dense cityscape; looking oblique right for probable aerosol haze over the North China plain. Some of the most detailed views of structure in haze-bearing air masses comes from the stagnant air over the plain), Western Mediterranean (opportunity to see Mt. Etna smoking, just left of track), and Western Mediterranean (pass along the Spanish and French coasts.  Looking south for panoramas of the Mediterranean with possible aerosols).
CEO images can be viewed at the websites
http://eol.jsc.nasa.gov
http://earthobservatory.nasa.gov

U.S. and Russian Segment Status (as of 1:06pm EST).

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

  • Elektron O2 generator is powered On (20 amp mode).  Vozdukh CO2 scrubber is On (manual mode 5).  U.S. CDRA CO2 scrubber is Off.  TCCS (trace contaminant control subsystem) is operating.  MCA (major constituents analyzer) is operating.  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) — 26.5; ppO2 (mmHg) — data invalid; ppCO2 (mmHg) — data invalid.
  • SM Transfer Compartment:  Pressure (mmHg) — 751; temperature (deg C) — 21.1.
  • FGB Cabin:  Pressure (mmHg) — 752; temperature (deg C) — 22.3.
  • Node:  Pressure (mmHg) — 743.89; temperature (deg C) — 24.4 (shell); ppO2 (mmHg) — n/a; ppCO2 (mmHg) — n/a.
  • U.S. Lab:  Pressure (mmHg) — 745.62; temperature (deg C) — 23.3; ppO2 (mmHg) — 171.2; ppCO2 (mmHg) — 3.5.
  • Joint Airlock (Equip. Lock):  Pressure (mmHg) — 745.73; temperature (deg C) — 31.7; shell heater temp (deg C) — 24.6, ppO2 (mmHg) — n/a; ppCO2 (mmHg) — n/a.
  • PMA-1:  Shell heater temp (deg C) — 23.2.
  • PMA-2:  Shell heater temp (deg C) — 15.4.

(n/a = data not available)

Propulsion System (PS):

  • Total propellant load available: 3573 kg (7877 lb) as of 5/29 [SM(774) + FGB(2547) + Progress(252)].  (Capability: SM — 860 kg; FGB — 6120 kg).

Electrical Power Systems (EPS):

  • Both P6 channels fully operational.  BGA (beta gimbal assembly) 2B and 4B both “directed” (non-solar tracking) mode (“sun slicer” position, for drag reduction).
  • SM batteries:  Batteries #4 is disconnected (failed); battery #8 has been replaced, in “Cycle” mode; all other batteries (6) are in “Partial Charge” mode (battery #2 is exhibiting degraded performance).
  • FGB batteries:  Battery #4 is disconnected; battery #5 is in “Cycle” mode; all other batteries (4) are in “Partial Charge” mode.
  • Plasma Contactor Unit PCU-1 in Standby mode; PCU-2 in Discharge 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-1 is operating; INT-2 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-2 MDM is Off; PL-1 MDM is Operational.
  • APS-1 (automated payload switch #1) and APS-2 are both On.
  • SM Terminal Computer (TVM): 3 redundant lanes (of 3) operational. Being upgraded.
  • SM Central Computer (TsVM): 3 redundant lanes (of 3) operational. Being upgraded.

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:

  • XPOP (x-axis perpendicular to orbit plane = “sun-fixed” [yaw: 0.5 deg, pitch: -6.8 deg., roll: 0 deg]), with CMG TA (thruster assist).
  • Solar Beta angle:  46.1 deg (magnitude decreasing).

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 (internal audio controller #1) being analyzed after self-test error.  IAC-2 is prime.]
  • Video subsystem operating nominally.
  • HCOR (high-rate communications outage recorder) is operating nominally.

Robotics:

  • SSRMS/Canadarm2 based at MBS PDGF #1 with Keep Alive (KA) power on both strings.
  • MBS: KA power on both strings. 
  • MT: latched at WS4, with KA power. 
  • POA: KA power on both strings.
  • RWS (robotics workstations): Lab RWS is Off; Cupola RWS is Off.

ISS Orbit  (as of this morning, 6:18am EDT [= epoch]):

  • Mean altitude — 388.6 km
  • Apogee — 392.5 km
  • Perigee — 384.7 km
  • Period — 92.33 min.
  • Inclination (to Equator) —  51.63 deg
  • Eccentricity — 0.0005725
  • Orbits per 24-hr. day — 15.60
  • Solar Beta Angle — 46.1 deg (magnitude decreasing)
  • Mean altitude loss in last 24 hours — 115 m
  • Revolutions since FGB/Zarya launch (Nov. ’98)  — 25823
  • 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.