STS-119

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Mission emblem
Mission emblem STS-119
Mission dates
Mission: STS-119
COSPAR-ID : 2009-012A
Crew: 7th
Begin: March 15, 2009, 23:44:44  UTC
Starting place: Kennedy Space Center , LC-39A
Space station: ISS
Coupling: March 17, 2009, 21:19 UTC
Decoupling: March 25, 2009, 19:53 UTC
Duration on the ISS: 7d, 22h, 34min
Number of EVA : 3
Landing: March 28, 2009, 19:13:17 UTC
Landing place: Kennedy Space Center, Lane 15
Flight duration: 12d, 19h, 29min, 33s
Earth orbits: 202
Track height: 350 km
Covered track: 8.48 million km
Payload: S6 segment
Team photo
v. l. Right: front: Tony Antonelli and Lee Archambault, back: Joseph Acaba, John Phillips, Steve Swanson, Richard Arnold and Kōichi Wakata
v. l. Right: front: Tony Antonelli and Lee Archambault,
back: Joseph Acaba, John Phillips, Steve Swanson, Richard Arnold and Kōichi Wakata
◄ Before / After ►
STS-126 STS-125

STS-119 ( English S pace T ransportation S ystem) is the mission name of a space flight of NASA 's US Space Shuttle Discovery (OV-103) . It was the 125th space shuttle mission, the 28th shuttle flight to the ISS and the 36th flight of the space shuttle Discovery.

The launch took place on March 15, 2009 at 23:43 UTC .

The STS-119 mission brought the S6 grid element to the International Space Station . This grid element was the last of the four solar modules to be installed. Another task of the team was connecting the solar module and the batteries.

team

ISS crew outward flight

ISS expedition 18

ISS crew return flight

ISS expedition 18

Preparations

After its last mission ( STS-124 ), the Discovery was brought back to its maintenance hangar , where routine follow-up examinations and damage repairs were carried out. The external tank for the flight arrived at the Kennedy Space Center on July 15, 2008 and was mounted between the solid fuel boosters . Originally, the tank and booster were intended for the STS-125 mission, which, however , had to be postponed for nine months due to technical difficulties with the Hubble space telescope , which had to be maintained. It was decided on October 30th to detach the Atlantis , which was already attached to the tank, from the tank so that the Discovery could use it for the STS-119 mission. Furthermore, the launch platform was cleared in time for the Ares IX test flight of the Ares I as part of the Constellation program .

The Discovery was transferred to the Vehicle Assembly Building on January 7, 2009 , then attached to the external tank. The entire shuttle was driven to launch pad 39A on January 14 , where the main payload, which had already been delivered on January 11, was expected. This was integrated into the payload bay over the next few days. On January 19, the crew came to the Terminal Countdown Demonstration Test to familiarize themselves with the safety precautions at the launch site.

Engine problems

A valve of the Discovery

After the STS-126 mission, damage was discovered on the cooling pressure valves of the main engines of the Endeavor , so that the counterparts of the Discovery were sent for an inspection to be on the safe side , but they passed without any errors. They were brought back to KSC on January 30th and then assembled. However, in order to understand the problem, further analyzes and tests were commissioned.

The Discovery on launch system 39A with the full moon in the background

On February 3rd, the leaders of the participating programs came together for the last of two Flight Readiness Reviews (FRR) to set a start date. However, they found that the analyzes regarding the valves would require further time and that a start would therefore not be possible before February 19. The FRR ended openly and was initially due to continue on February 14, shortly after a special meeting. This meeting was planned for February 12th, but should be postponed by one day, which also affected the start date - it was now on February 22nd. During the special meeting it was determined that progress had been made on the valve problem but that time was still needed for analysis. Thus, the date for the FRR was set to February 20th and the provisional start date to February 27th. However, during this meeting it was decided to postpone the start, as the test results were still not satisfactory. A new start date was not announced, but a meeting was planned for February 25th. Instructions were given on February 24th to replace all valves with valves with fewer inserts. On March 4th, managers and technicians of the space shuttle program came together to see the progress of the work. They decided to move on to the Flight Readiness Review two days later . Following this third FRR, March 12, 01:20 UTC was approved as the first launch opportunity. The crew arrived at the Kennedy Space Center on March 8, and the countdown began a little later .

Mission history

Start, rendezvous and pairing

The junction of the drain lines

The first attempt to start on March 12th ended while the external tank was being refueled. It was noticed that there was a leak in the hydrogen discharge line and the test was therefore discontinued at 16:37 UTC. The external tank was then emptied. Another attempt to take off was to be made on March 13th at 00:54 UTC, but was canceled in order to have more time to analyze the problem, which had never occurred in this form before. After the reason for the leak, a defective valve, had been found, the new start date of March 15 at 23:43 UTC was targeted. Previously, the defective valve was exchanged for a new one.

Due to this renewed postponement, one of the four planned spacecraft missions had to be canceled as the shuttle must have left the station in good time before the docking of Soyuz TMA-14 , which was scheduled to take off on March 26, 2009.

Start of the discovery

There were no problems whatsoever during refueling on March 15th. The new valve worked perfectly even after being opened and closed several times. Only a small problem occurred at the connection point of the fuel lines from the tank to the shuttle. There the pressure of a helium shielding gas system was close to the lower limit value, but could be set manually on the starting system. The helium prevents ice formation at the connection point. The crew left the Operations and Checkout Building as planned and boarded the orbiter, which was ready for launch. Some time later the hatch was closed and the launch system cleared.

Shot of the bat on the external fuel tank during the shuttle launch

During the countdown it was discovered that a bat had perched on the side of the external fuel tank facing away from the shuttle . NASA checked whether this could pose a safety risk for the shuttle if it were to fall against the heat shield during takeoff. After a brief investigation, this danger could be ruled out and the start with the bat on the tank was permitted. When analyzing photographs of the shuttle launch, she was identified as a bulldog bat and found that she was still on the tank during launch. Due to the shuttle's acceleration, it is likely that it was torn off shortly after take-off due to the resulting increasing air resistance and ended in the hot exhaust gases from the main engines .

As there were no further technical problems and the weather was perfect, the Discovery started at 23:43 UTC as planned. The solid fuel boosters were dropped two minutes after take-off, the main engines were deactivated after eight minutes and the external tank was dropped ten seconds later.

The crew spent the rest of the day preparing the Discovery for space flight. This included opening the loading bay doors and activating the RCS maneuvering drives and the robot arm . Furthermore, the orbiter was lifted 60 kilometers by the engine firing and moved from the initially powerful elliptical orbit into a more circular orbit.

The second day of the flight (March 17th) was all about various inspections. The most important of these was the examination of the heat shield for damage to the leading edge and tip of the space shuttle. For this purpose, an extension of the robot arm, the Orbiter Boom Sensor System with specially designed instruments, was used. In addition, the spacesuits that should be used during the three exits were checked and prepared as far as possible. Preparations for the transfers between the shuttle and the station as well as the docking were also made.

During the day it was discovered that the Discovery ergometer had a defect. The crew uses it to counteract muscle wasting during flight. Until the device was repaired, the crew had to resort to alternative training methods and the facilities of the ISS.

The Discovery during the RPM on one of the photos the ISS crew took to inspect the shuttle

The connection of the shuttle was scheduled for the third day of the flight (March 17th). For this purpose, several engine starts were carried out over the first half of the day in order to bring the Discovery onto an appropriate intercept course. About an hour before the docking, the Discovery was 200 m below the station to perform the Rendezvous Pitch Maneuver (RPM), a 360 ° backward roll. During this maneuver, the crew of the ISS took high-resolution photos of the lower heat shield of the shuttle using 400 mm and 800 mm lenses, which were then checked for damage. The start of this maneuver was delayed by several minutes when communication with the station was unexpectedly lost. This has been attributed to faulty headsets. After the ISS was able to receive calls again, but not send them, the RPM was started, but communication was lost again, so that the ISS crew was not informed of the official start of the photo session. So they started photographing the heat shield on their own. According to the RPM, the Discovery went 70 meters in front of the station and slowly began to approach it. The coupling finally took place at 21:20 UTC. An hour and 49 minutes later, the hatches between the spacecraft were opened and transfer operations began. The exchange of the Soyusseat of Sandra Magnus against that of Kōichi Wakata took place around 01:00 UTC on March 18, whereby they changed the crew membership.

Working on the ISS

The S6 segment on the Canadarm2 in the parking position before assembly on the following day of the flight

On the fourth day of the flight (March 18), work began on installing the S6 segment. For this purpose, several maneuvers were carried out with the robot arms of the shuttle and the station. First, Canadarm2 , controlled by John Phillips and Sandra Magnus, seized S6 and removed the segment from the payload bay. S6 was then passed to the shuttle's robotic arm so that Canadarm2 could be moved to the starboard end of the station with no risk to the station's balance or accelerated wear on the gyroscopes . There S6 was handed over again and brought into a parking position, in which it was left until the start of the exit the next day.

Inside the station, in addition to transfer activities and the operation of the robotic arms, preparations for the exit were made, which was carried out by Steven Swanson and Richard Arnold . The spacesuits were transferred to the Quest station airlock , assembled and refueled with oxygen. The tool bags were also prepared. After a preparatory briefing, Swanson and Arnold went into the airlock to breathe pure oxygen overnight under reduced air pressure. This so-called campout reduces the level of nitrogen dissolved in the body tissue and thus prevents decompression sickness .

Swanson (center) during the first exit

The fifth day of flight (March 19) began with the final preparations for the upcoming first exit. While Swanson and Arnold put on their spacesuits and checked them for the last time, Phillips and Wakata moved the station arm so that S6 was then only about 1.6 meters away from its final position. At 17:16 UTC, the astronauts switched to internal energy supply in the airlock of their spacesuits, marking the beginning of a US-based exit. They then went to the starboard end of the station and instructed Phillips on the S6 assembly so that the segment reached its final position at 18:17 UTC. Then they began to attach the segment and connect the wiring. Various starting brackets and heating mats were also removed and the segment's own radiator and the boxes in which the collectors are stored were extended. The exit ended after six hours and seven minutes at 23:23 UTC. The four removed thermal covers were disposed of as space debris ( SatCat 34605 to 34608) and burned up in the earth's atmosphere between March 31 and April 5 .

The unfolding of the collectors began before the beginning of the sixth day of flight (March 20). Both the front (3B) and the rear (1B) collector were extended around a so-called bay, the length of two cells attached to one another, so that the collectors could adapt to the space environment. Under the eyes of both crews, 1B was then extended to 49% and exposed to solar radiation in this position for an orbital day (about 40 minutes). This should heat the collector and thus loosen any adhesions between the panels. The collector was then fully extended. The same procedure was used to extend 3B. In the meantime, a deformation was noticed on the collector, which, however, should not hinder the complete extension. The crews then continued with other work. This included the repair of the shuttle's ergometer, in which a component got stuck. Repairs have also been made to the urine processing system, part of the US water recycling system. After the initial start-up during the STS-126 mission, a defect was found in a centrifuge, which is why the system did not work correctly. Finally, the preparations for the second exit began. Accordingly, Steven Swanson and Joseph Acaba spent the night in the airlock and conducted another campout.

Steven Swanson during the assembly of the GPS antenna

The disembarkation began on the seventh day of the flight (March 21) at 16:51 UTC after one of the station's four gyroscopes was deactivated in preparation for the planned work. Swanson and Acaba made their way to the P6 segment at the left end of the station after exiting the airlock. There they were preparing to replace batteries during the next ISS shuttle mission STS-127 . They tested the tools and stowed them on the spot. During this work, one of the three remaining gyroscopes failed, which meant that the minimum requirements for position control were not met and this task was taken over by the Discovery during the rest of the exit. Then they went to the P3 segment to deploy a docking point for external payloads (UCCAS). However, it was not possible to extend it completely, this was attributed to a locking bracket bolt. After a few attempts, they broke off the work and divided up. Swanson went to the Kibo segment of the station and installed the last of two GPS antennas that were to be used for the approach of the Japanese HTV . Acaba meanwhile began to photograph the S1 and P1 radiators in the visible and infrared light spectrum. Photographic documentation of the radiators was done to better understand how a crack in one of the starboard panels would affect overall performance. After installing the GPS antenna, Swanson went to the Z1 segment to work on a connection panel for the power supply for the gyroscopes. However, these were interrupted after some time and Swanson was sent back to P3 to secure the tying point with some ropes. The exit ended after exactly 6 hours and 30 minutes at 23:21 UTC. Due to the problems with the P3 coupling point, the extension of a counterpart at S3 had to be canceled.

Inside the station, the urine processor was run dry. Station commander Michael Fincke reported that the volume level was significantly lower compared to the original part.

The first part of the eighth day of flight was made available to the crew members to recover from the exertions of the past few days. They used the time to have conversations with their family members. Fincke meanwhile continued work on the urine processor and carried out a test run with urine. The spare part worked perfectly, but the speed of the urine was greatly reduced. The work was stopped for the time being and the unit's filter was replaced some time later. A new test was then started.

At 20:00 UTC an evasive maneuver was started to avoid a part of the wreckage of a Chinese satellite with a diameter of about 10 cm. It had the same orbit height as the station, but instead of 51.6 ° an orbit inclination of 98 ° and would have come dangerously close to the station twice per orbit during the upcoming exit and the following days. Between 20:00 UTC and 20:30 UTC, the Discovery performed a maneuver that turned the station 180 ° and brought it into the undocking position. She held this position for three hours, reducing the speed of the complex enough to avoid the wreckage. Since more precise data on the trajectory of the wreckage were only available later, but due to the accelerations that occur, such maneuvers cannot be carried out at the same time as a space exit, NASA decided to carry out the maneuver preventively before the exit. After the maneuver, the Discovery turned the complex back into flight position and preparations for the final exit began. Among other things, Arnold and Arcaba received more detailed information regarding the work on P3. Based on tests in the Neutral Buoyancy Laboratory (zero buoyancy laboratory) at the Johnson Space Center in Houston, it was assumed that the problem could be solved with greater force. The team then went to the Quest airlock for a campout.

The astronauts fixing the CETA in their new position

The third exit began on March 23, the ninth day of the flight, at 16:34 UTC. Initially, Phillips and Wakata maneuvered the CETA platform from P1 to S1, where it was then locked into place by Arnold and Arcaba. Then they tried again on the UCCAS adapter. The protruding bolt was not the reason for the blockage, but the error could not be remedied even with greater effort. The two astronauts then fixed the adapter in its half-extended position with ropes that can withstand space conditions for long periods of time. As the cause of the problems was still unclear, the assembly of the S1 counterpart was also canceled. Then Acaba went back to the CETAs to attach a connector. Arnold went to the B-end of the robot arm to lubricate it. After a few additional tasks, the exit ended after 6 hours and 27 minutes at 22:04 UTC and brought the total time of the spacecraft operations on this mission to 19 hours and 4 minutes.

The system for extracting water from urine was successfully tested with liquid and the extracted water was brought back to earth by the Discovery for laboratory tests.

On flight day ten (March 24th) the last transfers between the Discovery and the ISS were carried out, which did not have to wait until the last possible time. At 14:00 UTC there was a question and answer session with US President Barack Obama , a school class and some congressmen. The crews held their traditional press conference at 17:00 UTC, with the rest of the day free for the space travelers of the Discovery.

The ISS after disconnecting Discovery

Flight day eleven (March 25th) began with the final transfers. Mainly it was about scientific results, which should be frozen as long as possible before they were brought on the Discovery. At 17:59 UTC, the crews then finished their work together and closed the hatches between the spacecraft. After a total of 9 days, 20 hours and 10 minutes, the Discovery undocked at 19:53 UTC and moved away from the space station. Then pilot Dominic Antonelli took control and flew the Discovery in a circle around the station so that the crew could document the progress of construction photographically. After this maneuver, the engines were fired and the Discovery began to move away from the station.

return

The preparations for the landing were made starting with flight day twelve (March 26). The crew began to stow loose objects and carried out another examination of the heat shield using the OBSS . On the 13th day of the flight (March 27), the focus was on testing the systems required for landing. This system included the wing hydraulics and the control nozzles. Other objects that were no longer needed were stowed away and a special reclining seat was set up for Sandra Magnus, who would suffer from muscle wasting after 137 days on the ISS. Furthermore, an engine ignition was carried out, which reduced the height of the shuttle.

Landing of the Discovery at Kennedy Space Center

The landing was scheduled for the 14th flight day (March 28) at 17:39:42 UTC on the Shuttle Landing Facility at the Kennedy Space Center. Accordingly, the cargo bay doors were closed shortly after 14:00 UTC. The first landing opportunity could not be used due to the weather conditions, as the maximum permissible peak wind speed of 46.3 km / h (25 knots ) for the landing was  exceeded. However, the weather should generally improve for the second landing attempt, so that the crew was given clearance for Deorbit Burn shortly before 18:00 UTC . The astronauts had consumed several liters of liquid beforehand in order to better adapt to gravity. The brake ignition began at 18:08 UTC and slowed the shuttle by 370 km / h. The landing took place at 19:13:17 UTC on runway 15 of the Shuttle Landing Facility. Shortly after landing, a security convoy drove to the space shuttle to cool it down and help the crew exit after they had shut down all the space shuttle systems. They also secured the time-critical experiments that returned with the Discovery. The Discovery was driven back to the Orbiter Processing Facility a few hours later to be prepared for its next mission, STS-128 .

See also

Web links

Commons : STS-119  - Album with pictures, videos and audio files

Individual evidence

  1. ↑ Clara Moskowitz: Bat Hung On For a Ride Into Space. In: Space.com. March 17, 2009, accessed March 23, 2009 .
  2. ↑ Bat Hung onto Shuttle During Liftoff. In: nasa.gov. NASA , March 17, 2009, accessed March 23, 2009 .
  3. ↑ STS-119 MCC Status Report # 01. In: nasa.gov. NASA, March 16, 2009, accessed March 23, 2009 .
  4. ↑ STS-119 MCC Status Report # 03. In: nasa.gov. NASA, March 17, 2009, accessed March 23, 2009 .
  5. ↑ STS-119 MCC Status Report # 05. In: nasa.gov. NASA, March 18, 2009, accessed March 23, 2009 .
  6. ↑ STS-119 MCC Status Report # 07. In: nasa.gov. NASA, March 19, 2009, accessed March 23, 2009 .
  7. ↑ STS-119 MCC Status Report # 09. In: nasa.gov. NASA, March 20, 2009, accessed March 23, 2009 .
  8. ↑ Object ID Query Results. Space-Track.Org, April 18, 2009, accessed on April 18, 2009 .
  9. ↑ STS-119 MCC Status Report # 11. In: nasa.gov. NASA, March 21, 2009, accessed March 23, 2009 .
  10. ↑ STS-119 MCC Status Report # 13. In: nasa.gov. NASA, March 22, 2009, accessed March 23, 2009 .
  11. ↑ STS-119 MCC Status Report # 15. In: nasa.gov. NASA, March 23, 2009, accessed March 23, 2009 .
  12. ↑ STS-119 MCC Status Report # 17. In: nasa.gov. NASA, March 24, 2009, accessed March 24, 2009 .
  13. ↑ STS-119 MCC Status Report # 19. In: nasa.gov. NASA, March 25, 2009, accessed March 26, 2009 .
  14. ↑ STS-119 MCC Status Report # 21. In: nasa.gov. NASA, March 26, 2009, accessed March 26, 2009 .
  15. ↑ STS-119 MCC Status Report # 23. In: nasa.gov. NASA, March 27, 2009, accessed March 27, 2009 .
  16. ↑ STS-119 MCC Status Report # 25. In: nasa.gov. NASA, March 28, 2009, accessed March 28, 2009 .
  17. ↑ STS-119 MCC Status Report # 27. In: nasa.gov. NASA, March 29, 2009, accessed March 29, 2009 .