Status Report

NASA Space Station On-orbit Status 20 Aug 2003

By SpaceRef Editor

August 20, 2003

Filed under ISS, ISS On-orbit status, NASA HQ, US

NASA Space Station On-orbit Status 20 Aug 2003 — iss

All ISS systems continue to function nominally, except as noted previously or below.

Crew continued the demanding task of loading the Progress 10P cargo vehicle with approved deorbit items, keeping track of stuff with the IMS (inventory management system). [Today’s timeline had 4 hrs. of crewtime blocked out for the two station residents. Ground specialists had uplinked a 45-entries list of items identified for disposal and coordinated through the normal process. For proper stability and control of the fully automated spacecraft, operating on pre-stored autopilot command algorithms, it is important that center of gravity and mass moments of inertia of the ship remain within prescribed limits. Careful documentation is used to assure proper ballasting.]

Ed Lu activated the MSG (microgravity science glovebox) and took up work again with the PFMI (Pore Formation & Mobility Investigation) experiment. [Today’s run used the PFMI-04 ampoule already installed in the MSG WV (work volume). The samples are seeded with bubbles and impurities that are visible inside the ampoule, and Ed was cautioned not to mistake the impurities for cracks in the ampoule. Background: Defects generated in solidifying (crystallizing) materials compromise desired material properties and science (for example, measurement of microstructural features, i.e., dendrite arm spacing, is inaccurate). The MSG investigation is intended to promote our understanding of detrimental porosity formation and mobility during controlled directional solidification processing in a microgravity environment. This is studied by utilizing a transparent material, Succinonitrile (SCN), so that direct video observation and recording of pore generation and mobility during controlled directional solidification can be made. SCN is particularly well suited for the proposed investigation because it is transparent, solidifies in a manner analogous to most metals, and has a convenient melting point. With toxicity level 0, its material properties are well known and it has been successfully used in previous microgravity experiments.]

Later, Ed Lu set up the SSC4 (station support computer #4) laptop, reconfiguring it for Airlock operations, and initiated the discharge of EMU batteries #2029 and #2030, used last week, as part of nominal battery maintenance. [The laptop-controlled discharge will be automatically terminated by the charger after ~24 hrs.]

Yuri Malenchenko prepared the daily IMS update (“delta”), while Ed Lu attended to the routine maintenance of the SM’s SOZh environment control & life support system as well as the regular daily status checkup of autonomously running Lab payloads (PCG-STES010, MAMS).

At 11:40am EDT, the crew conducted a 20-min. interactive PAO/educational TV downlink to NASA Earth Crew members at JSC, as part of NASA’s Teaching from Space Program (TSP). [NASA’s Earth Crew consists of more than 23,000 students who have signed up through the agency’s Educator Astronaut Web site. The students help NASA plan and conduct scientific explorations without ever leaving the ground. Earth Crew students receive e-mail updates about new projects, participate in exploration-related activities, and even provide suggestions to NASA to help plan upcoming missions.]

Resupply propellant brought up by Progress 10P was transferred to the FGB. [At 2:25am EDT, MCC-Moscow’s automated onboard sequencer inhibited the Progress’ approach and attitude control thrusters (DPO), transferring control to the integrated propulsion system (ODU) thrusters of the Service Module (SM). After an accelerometer test in SM and FGB, the propellant system of the three modules was configured for propellant transfer. Fuel and oxidizer was then pumped from the 10P tanks to the FGB storage tanks via plumbing running through the SM. The procedure took about 3 hrs.]

During the prop transfer, Moscow also conducted a 10-min. test of the Kurs-P (passive part of the automated approach and docking radar) from the SM aft end, in preparation for the docking of the next cargo ship, 12P/Progress M-248, on 8/30.

At 1:05pm, ISS attitude control was handed over from the U.S. segment (USOS) to the Russian motion control system (MCS). At 1:20pm, the SM thrusters maneuvered the station from solar-oriented XPOP (x-axis perpendicular to orbit plane) to earth-pointing LVLH (local vertical/local horizontal). Control authority then returned to the USOS CMGs.

Yesterday’s transition from the Lab’s INT-1 MDM computer to the INT-2 MDM was successfully completed, with only minor issues. [After the transition, there was an MDM power cycle. Data is being downlinked for analysis.]

Last night two RPCMs (remote power controller modules) failed in the Lab, with no overcurrent spikes being observed. Based on the signature, a hybrid FET (field effect transistor) failure is suspected. [The systems controlled by these RPCMs include the Lab’s ATU-2 (audio terminal unit #2) and the UHF (ultra-high frequency) radio. Neither system is critical at this time. Specialists are reviewing the data to determine failure cause, impacts, and required response.]

The electric ENA pump removed yesterday by the crew from a replaceable pump panel (SPN) of the Russian STR thermal control system was a pump that malfunctioned approximately 10 months ago. The SPN was not the KOB-2 loop pump panel that failed several weeks ago. The removed ENA will be returned on Soyuz for analysis.

Both crewmembers completed their daily 2.5-h program of physical exercise (aerobic & anaerobic) on TVIS, RED and on the Russian VELO cycle ergometer with load trainer.

By MCC-M ground command, the Lab’s VES (vacuum exhaust system) and VRS (vacuum resource system) valves were opened to gather data on PGT (Pirani Gauge Transducer) pressure sensors.

The USOS MCA (major constituents analyzer) is activated daily by remote command for a 15 min. rapid atmospheric sampling of the Airlock (A/L) prior to the station oxygen (O2) repress from Progress 10P. [During past O2 represses, the ppO2 (oxygen partial pressure) caution limit was reached in the Lab. This made the MCA go automatically into rapid sampling, which caused communications problems between it and the INT MDM. Commanding the MCA to rapid A/L sampling before the repress prevents these problems.]

As long as there is gaseous O2 in Progress 10P, station atmosphere is being refreshed from its tankage (rather than from the Elektron water electrolysis apparatus) whenever ppO2 has decreased to 160 mmHg. After 10P undocking, repress O2 will also be transferred from Progress 11P.

A conjunction (close encounter) with an Ariane rocket body occurred this afternoon at 2:30pm EDT. Final predicted separations were 5 km downtrack (in front), 200 m above, and 100 km crosstrack (to the side), i.e., in the “green” zone. [MCC-H ballistics experts worked the conjunction predictions since yesterday morning. Originally, the debris was predicted to pass within 800 m, based on only one tracking pass and very fluctuating forward-calculation (which requires six orbital parameters). In particular, determination of the object’s orbit plane, versus the station’s plane, is extremely difficult with limited skin-tracking data. Yesterday’s notification by USSPACECOM came too late for Moscow to calculate and uplink steering parameters for a debris avoidance maneuver (DAM). New predictions this morning first had the object outside the 5-km threshold limit, then inside at 4.6 km. Later in the day, as tracking data stabilized, miss distance moved out again, by Noon to 5.6 km, i.e. in the “green” zone. If a DAM is not performed and predicted miss distance is less than 5 km, the applicable Flight Rule (B4-1) requires the crew to enter the Soyuz return vehicle. It is not necessary to actually close the hatch but the crew should be prepared to close it quickly. Retreat to the Soyuz was not necessary today.]

Today’s CEO (crew earth observation) targets, taking into account the current XPOP attitude and the change to LVLH at 1:20pm EDT, and including the targets of the Lewis & Clark 200-year memorial locations, were Rome, Italy (looking a touch left of track), Moundsville W VA (LEWIS & CLARK SITE: The explorers performed some their earliest science observations here), Pomeroy, WA (LEWIS & CLARK SITE: On their return eastward, the explorers decided to go overland in order to avoid battling upstream against the strong Snake River. Looking left of track), Cayuse, Umatilla (LEWIS & CLARK SITE: This relatively large site is the heart of the Homeland Heritage Corridor and includes the Umatilla Indian Reservation. Looking left of track), Great Falls, MT (LEWIS & CLARK SITE: The Missouri River drops more than 400 feet in ten miles here. The explorers spent more than a month here in June-July 1805, and noted the value of this site for hydro-power generation. Now the Ryan Dam occupies the site. The site lies on the river, at the city of Great Falls, where the highway crosses the river, all at nadir), Maro reef, Hawaii (nadir pass; coral reef), Ontario fires (Dynamic event. Fires have been making the news for weeks and this smoke pall is one of the biggest we have seen. Regional smoke pall starts in western Ontario and sweeps east hundreds of miles over James Bay into Quebec. Looking left of track), Gulf of Maine plankton (looking left and right of track), and Osaka, Japan (nadir pass)..
CEO images can be viewed at the websites

See also the website “Space Station Challenge” at
http://voyager.cet.edu/iss/

ISS Orbit (as of this morning,11:36am EDT [= epoch]):