Q&A with George Ricker, principal investigator for the TESS mission (members only)

Preparations for the planned liftoff Thursday of a SpaceX Dragon capsule with a four-person crew to the International Space Station cleared another readiness review Tuesday at NASA’s Kennedy Space Center in Florida, but officials are tracking marginal wind and sea conditions in downrange abort zones in the Atlantic Ocean that could force a launch delay.

The mission will be the 14th time that a SpaceX Dragon spacecraft carries humans to the International Space Station. The mission launched on Friday, March 14, at 7:03 p.m. EDT (2303 UTC).

Moving closer toward launch Monday with a South Korean communications satellite, a SpaceX Falcon 9 rocket fired its nine Merlin main engines Thursday on a launch pad in Florida in a key preflight readiness test.