Spacecraft built by SpaceX have been servicing the International Space Station since 2012, and now NASA has chosen SpaceX to build the spacecraft that’ll take the station down to its doom in 2030.
The space agency announced today that SpaceX has been selected to develop and deliver the U.S. Deorbit Vehicle that will provide the capability to push the station into a fiery but controlled descent through the atmosphere. The deed will have to be done in a way that makes sure any debris falls harmlessly in an unpopulated area — for example, a remote part of the Pacific Ocean known as Point Nemo.
NASA laid out its plan for deorbiting the space station at the end of its operating life two years ago. At the time, mission planners suggested that Russian Progress supply ships or Northrop Grumman’s Cygnus cargo spacecraft might play a part in the denouement.
Today’s announcement makes clear that a SpaceX craft will take on the curtain-closing role. However, NASA will take ownership of the U.S. Deorbit Vehicle once it’s developed, and operate it through the final mission. No astronauts will be aboard the station during the robotically guided re-entry, and the U.S. Deorbit Vehicle is expected to break up along with the rest of the space station.
NASA said the single-award contract has a total potential value of $843 million. Launch service will be covered in a future procurement.
The ISS is a 15-nation collaboration operated by five space agencies — NASA, the European Space Agency, the Canadian Space Agency, Russia’s Roscosmos and the Japan Aerospace Exploration Agency. Each of the agencies is responsible for managing and controlling the hardware it provides, but the safe deorbiting of outmoded hardware is the responsibility of all five agencies.
For what it’s worth, Russia has committed to continued ISS operations through at least 2028, while the other four agencies have committed to operations through 2030.
The International Space Station is already showing its age: For example, NASA and Roscosmos have been keeping an eye on a long-running air leak in the station’s 24-year-old Zvezda module, which was one of first pieces of the space station to be launched.
NASA expects commercial space stations — such as Axiom Station, Orbital Reef or Starlab — to be in operation by the time the International Space Station has run its course. There had been some talk of splitting off sections of the ISS for reuse in a commercial outpost, but a NASA white paper seemed to downplay that option.
“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,” Ken Bowersox, NASA’s associate administrator for space operations, said in today’s news release. “This decision also supports NASA’s plans for future commercial destinations and allows for the continued use of space near Earth.”
Neither NASA nor SpaceX released a design concept for the U.S. Deorbit Vehicle. However, SpaceX has a wide array of spacecraft designs it could start with, including its Starship super-rocket (currently in testing) and its Dragon XL cargo vehicle (which NASA selected for supplying its future Gateway in lunar orbit). Who knows? It might even be a hopped-up version of the Dragon capsule that started delivering cargo to the ISS way back in 2012.
Update for July 17, 2024: Sure enough, SpaceX’s design concept for the Deorbit Vehicle is basically a SpaceX Dragon capsule with an enhanced trunk section. During a July 17 briefing, SpaceX’s Sarah Walker said the spacecraft will have 46 Draco thrusters — including the usual 16 for attitude control and an additional 30 to push the ISS to its doom. It’ll carry six times as much propellant as the standard-issue Dragon, and have three to four times as much power.
NASA’s deorbit plan calls for launching the Deorbit Vehicle and docking it to the ISS about 18 months in advance of the final re-entry maneuvers. The space station would be allowed to drift down gradually from its normal orbit due to atmospheric drag.
About six months before the end, the last crew would depart for Earth, and the uncrewed station would continue its gradual descent. When the altitude reaches about 220 kilometers (137 miles), the Deorbit Vehicle would fire its thrusters for the final series of burns, sending the station into a controlled re-entry.
In a source selection statement, NASA said Northrop Grumman also put in a bid to build the Deorbit Vehicle, but SpaceX’s concept was considered less risky.
