SpaceX's Crew-12 launch to the International Space Station has slipped to Friday due to unfavorable weather along the eastern flight path, pushing back the mission by a day from its original Wednesday target. This delay opens the door for United Launch Alliance (ULA) to launch its new Vulcan rocket on its first national security mission of the year. The Vulcan, making only its fourth flight overall, is set to lift off from Cape Canaveral's Space Launch Complex 41 on Thursday morning.

The USSF-87 mission carries multiple payloads for the Space Force's Space Systems Command, including the Geosynchronous Space Situational Awareness Program satellite designed to monitor space threats. ULA's plans to ramp up launches in 2025 fell short, with only six missions flown including the lone Vulcan flight while SpaceX launched 101 times. The company faces a significant backlog of over 20 national security missions due to delays in Vulcan development and the retirement of its older rockets.