|
MLM Nauka docks to ISS, malfunctions shortly thereafter
[NasaSpaceFlight.com] Russia’s Multipurpose Laboratory Module (MLM) Nauka, meaning “science,” has defied the odds to successfully dock to the ISS after a long and arduous journey dating back over 20 years and a problematic propulsion system after launch which had threatened the success of the mission. The docking was not without issue, with Russian cosmonauts noting that Nauka wasn’t on the correct course less than an hour before docking; however, a retro burn quickly corrected the issue. After also troubleshooting an issue with the TORU manual docking system, Nauka successfully docked in automated fashion to the Zvezda service module’s nadir port at 09:29 EDT / 13:29 UTC, marking the first major expansion to the Russian segment for over 20 years. UPDATE — July 29, 5:34 EDT / 21:34 UTC At 12:34 EDT / 16:34 UTC, the ISS’s systems registered a divergence from the nominal attitude orientation. The station’s gyros attempted to correct the attitude error but couldn’t. At 12:42 EDT /16:42 UTC, the ISS’s attitude departure exceeded limits and a Loss of Attitude emergency was declared, giving NASA and the ISS top priority through the TDRS (Tracking and Data Relay Satellite) communications network in geostationary orbit. At this time, the ISS was commanded to free-drift, the gyros were shutdown, and emergency control was handed to the Russian segment and the Zvezda service module. Zvezda likewise tried to correct the orientation of the Station, fighting against Nauka as the new module continued to fire its thrusters. Over the next 45 minutes, Russian controllers attempted to cease the thruster firings from Nauka, which were occurring without command. During this event, the ISS attitude movement never exceeded 0.5 degree per minutes and the crew did not feel the event. according to Russian media reports, Nauka burned through its remaining fuel during this thruster event. At 13:29 EDT / 17:29 UTC, with Nauka’s thrusters no longer operating, Russian controllers were able to use Progress MS-17’s thrusters to get the Station back in attitude control and returned to a stable orientation. As a result of the need to evaluate the station, Starliner’s OFT-2 mission, which was scheduled to launch on 30 July, has been postponed to no earlier than Tuesday, 3 August 2021 at 13:20:10 EDT / 17:20:10 UTC. Posted by: 3dc 2021-07-30 |
| http://www.rantburg.com/poparticle.php?ID=608491 |