Q&A with Keith Gendreau, principal investigator of the first X-ray space communications experiment (members only)

Four commercial space fliers who launched from NASA’s Kennedy Space Center on Axiom’s second private astronaut mission Sunday arrived at the International Space Station on a SpaceX crew capsule Monday to start an eight-day stay full of scientific experiments, student outreach events, and sightseeing.

SpaceX scrubbed a Falcon 9 launch attempt Thursday to evaluate a “slightly high” pressure reading in the rocket’s upper stage liquid oxygen tank, and officials have rescheduled the company’s final mission of the year for Saturday morning.

United Launch Alliance and SpaceX beat out Northrop Grumman and Jeff Bezos’ Blue Origin for billions of dollars in U.S. military rocket contracts, and will share the load in launching the Pentagon’s highest-priority national security space missions through 2027, officials announced Friday.