NASA Is Taking Bids For A $1B Space Tug Mission To Crash The ISS Into Earth

NASA has sent a request for proposal for an estimated $1B US Deorbit Vehicle (USDV), a spacecraft aimed at deorbiting the International Space Station (ISS) and ultimately safely crashing back to Earth. The United States, Japan, Canada, and the European Space Agency (ESA) have all committed to operating the station through 2030, with Russia agreeing to do so through 2028.

ISS has been in continuous operation since November 2000. It has been inhabited by an international crew of seven people (sometimes more) who live and work on the space station while traveling five miles per second, orbiting Earth about every 90 minutes. During its lifetime in space, the primary structure of the space station has been affected by dynamic loading and orbital thermal cycling, as well as other factors. Because of the years of wear and tear, NASA and its international partners decided to end ISS's time in space at the end of this decade.

The plan is to deorbit ISS in a controlled manner so as to avoid populated areas. NASA says that the safe deorbit of the ISS is a shared responsibility of all five space agencies. With the end of the decade quickly approaching, NASA and the Johnson Space Center have issued a Final Request for Proposal for the United States Deorbit Vehicle Procurement, a 'space-tug' craft powerful enough to pull the ISS from its orbit and send it crashing safely back to Earth.

Jonathon McDowell remarked in an interview with the DailyMail, "Here's what's tricky. You can fly the ISS safely down to an altitude of about 250km. After that, you need this special USDV ship to take over the steering - it's like driving down a motorway with a lot of wind gusts - you need a lot of muscle power to stay on the road." He added, "If you ever lose control and the ISS starts tumbling, you're in trouble because then you can't reliably point the rocket engines in a particular direction."

NASA says it chose to deorbit the ISS instead of disassembling it in space and returning it to Earth because the truss structure was not designed to be easily disassembled in space. The space station covers an area about the size of an American football field, which required 27 flights by NASA to assemble. The space agency added that any disassembly effort to return individual components safely would face significant logistical and financial challenges. It also decided against boosting the massive structure into a higher orbit.

Proposals for the USDV will be due no later than November 17, 2023, along with Past Performance, due no later than October 16, 2023. Those who meet the deadline will then wait for a confirmation email acknowledging their reservation and further instructions.