Record Number of Astronauts on ISS With Successful Crew Dragon Docking

The SpaceX Crew Dragon carrying NASA’s Megan McArthur and Shane Kimbrough, the European Space Agency’s Thomas Pesquet, and the Japan Aerospace Exploration Agency’s Akihiko Hoshide has successfully docked with the International Space Station (ISS) early Saturday morning. The successful docking of Crew-2’s Crew Dragon, known as “Endeavour,” temporarily brings the number of astronauts and cosmonauts on the ISS up to a record-setting 11.

Crew-2 successfully launched from NASA’s Cape Canaveral before dawn on April 23. Once on orbit, it performed a series of burns to bring its orbit in line with the International Space Station. This is the second of a series of six crewed flights to the International Space Station that SpaceX will conduct for NASA as part of one of its contracts with the space agency.

The contract is part of NASA’s Commercial Crew program designed to provide a privately developed and owned replacement for the Space Shuttle, which was retired in 2011. Although it has annoyed Russia that its monopoly on crewed launches to the International Space Station is now broken, SpaceX’s work represents a cost savings for NASA of $25 million a seat compared to launches on the Russian Soyuz.

SpaceX can provide these cost savings due to its development of reusable hardware. SpaceX previously used Endeavour for the Demo-2 mission, for instance, though it has since been upgraded based on data and technical reviews from the final test mission to demonstrate the Crew Dragon’s operational readiness.

Most notably, SpaceX technicians made note of greater than expected wear and tear in parts of the Crew Dragon’s heat shield during post-flight inspections of the spacecraft. The heat shield has since been shored up in those areas. Concerns about the heat shield, which protects astronauts from the excessive heat produced by the friction of reentry, dates back as far as the Mercury Program’s “Friendship 7” mission, during which John Glenn became the first NASA astronaut to orbit Earth. A false alarm had caused concern that the heat shield on the Mercury spacecraft had come loose.

The reusable hardware may have also been a factor in NASA’s selection of SpaceX’s lunar lander proposal for the Artemis Program. The $2.89 billion fixed-price contract was reportedly based partly on a bid that was far lower than those placed by Blue Origin and Dynetics. SpaceX has also passed several rounds of technological readiness reviews.

The Crew-1 astronauts are still on board the ISS and are expected to return home in one of NASA’s classic “splashdowns” on Wednesday. The splashdown method had previously been used for NASA’s Mercury, Gemini, and Apollo missions of the 1960s and 1970s. It was also used for the Demo-2 mission, which was the final test of the Crew Dragon’s ability to support astronauts and ferry them to the International Space Station.

Earlier this month, Crew-1 had moved its Crew Dragon, Resilience, to another port to make room for Crew-2 to dock to the space station’s zenith port. While space station crews have previously had to relocate the Russian Soyuz to make room for incoming spacecraft, this was a first for the SpaceX Crew Dragon. The International Space Station’s docking ports have seen a lot of action in recent weeks, including the arrival of the Russian Soyuz MS-18 and an uncrewed SpaceX Cargo Dragon.

During Crew-2’s six-month stay on the International Space Station, the crew will perform valuable scientific experiments and make upgrades to the space station’s solar panel array. This includes the installation of flatter solar panels that they can unroll like a yoga mat and continuing studies of the effects of microgravity on human organs and tissues. These studies could assist with the development of new therapies for health conditions that are common in seniors and the mitigation of “space aging” for long-duration missions like journeys to Mars.