SpaceX Wins $843M NASA Contract To Build A Deorbit Vehicle That Will Destroy ISS
Former President Ronald Reagan approved a budget in 1984 for the development and deployment of the space station. During the years between 1984 and 1993, the ISS was designed, with elements of the Station being constructed in the late 80s throughout the US, Canada, Japan, and Europe. It was not until 1998 that the elements of the new ISS began being taken into low-Earth orbit to begin construction.
Since 2000, when the first crew arrived on the ISS, more than 270 astronauts have visited the space station to perform science experiments and other research. Now, with SpaceX having formally been awarded with the contract to build the spacecraft that will deorbit the ISS in 2030, the iconic and historic space station’s ultimate demise becomes more of a reality, as NASA and its international partners transition to a future of commercial destinations.
“Selecting a U.S. Deorbit Vehicle for the International Space Station will help NASA and its international partners ensure a safe and responsible transition in low Earth orbit at the end of station operations. This decision also supports NASA’s plans for future commercial destinations and allows for the continued use of space near Earth,” remarked Ken Bowersox, associate administrator for Space Operations Mission Directorate at NASA Headquarters in Washington. “The orbital laboratory remains a blueprint for science, exploration, and partnerships in space for the benefit of all.”
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Ultimately, the primary objective during the space station’s deorbit operation will be the safe re-entry of the space station’s structure into an unpopulated area in the ocean. NASA has stated that the chosen approach for safe decommissioning is a combination of natural orbital decay, intentionally lowering the altitude of the station using current propulsion elements, and the execution of a re-entry maneuver for final targeting, along with controlling the debris footprint. The final maneuver is where the SpaceX deorbit spacecraft will come into play.
Because of the high propellant requirement of the final maneuver, Earth’s natural atmospheric drag will be used as much as possible to lower the station’s altitude while setting up deorbit. Finally, once all crew have safely returned to Earth, and following small maneuvers to line up the final target ground track and debris footprint over an uninhabited region of the ocean, space station operators will command a large re-entry burn that will provide the final push needed to ensure a safe atmospheric entry into the target footprint.
NASA engineers expect breakup during re-entry to occur as a sequence of three events. The first being the solar array and radiator separation, followed by the breakup and separation of intact modules and the truss segment, and finally individual module fragmentation and loss of structural integrity of the truss. During re-entry, the external skin of the modules is expected to melt away and expose the internal hardware to rapid heating and melting. The majority of station hardware is expected to burn up or vaporize during re-entry, whereas some denser or heat-resistant components, such as the truss segments, are expected to survive re-entry and splash down in the targeted safe zone.
While SpaceX will be responsible for designing and constructing the deorbit vehicle, NASA will take ownership following its completion and throughout the mission.
