NASA’s Johnson Space Flight Center has put out a request for designs for a US Deorbit Vehicle (USDV), previously referred to as a “space tug,” to trigger and control the ISS’ final spiral into Earth’s atmosphere when the space station is decommissioned in 2030.
“The USDV shall rendezvous and dock with the ISS as well as perform ISS attitude control, ISS translational maneuvers, and the final ISS orbit shaping and reentry burns,” NASA explained in the notice.
The space flight agency will hold a Virtual Pre-Proposal Conference about the request on October 3 and proposals are due by November 17, the notice also said. The space vehicle is expected to take years to test and certify.
In this photo provided by NASA, backdropped against clouds over Earth, the International Space Station is seen from Space Shuttle Discovery as the two orbital spacecraft accomplish their relative separation on March 7, 2011
© AP Photo
According to a plan put forward last year, the spacecraft would be launched just days before the ISS was to plunge into the sea, as its orbit decays below 140 miles altitude. NASA noted in a September 20 blog post that Russia’s Progress cargo vehicles, which are sometimes used to give the ISS’ orbit a boost upward, would not be up to the task of bringing the whole station down in a controlled way, which had been a previous deorbiting plan.
This past spring, NASA requested $180 million in its fiscal year 2024 budget for the USDV contract, but budget feuds on Capitol Hill resulted in major cuts to the space agency’s funds for FY2024, which begins on Sunday. The vehicle is not mentioned in NASA’s 2024 budget estimates released last month, although plans for deorbiting the ISS are.