Watch a replay of the Falcon 9 launch with Dragon

The Atlas 5 rocket that will send NASA’s Perseverance rover toward Mars next month aced a countdown rehearsal Monday at Cape Canaveral, helping ensure the United Launch Alliance-built rocket is ready for liftoff during the rover’s 23-day launch window.

A mysterious space vehicle described by Chinese state media as an experimental reusable spacecraft completed a two-day flight in low Earth orbit Sunday.

The launch of a NASA research satellite built to probe conditions along the boundary between Earth’s atmosphere and space has been tentatively rescheduled for no earlier than Wednesday, pending the conclusion of a review of unexpected data signatures discovered on the first stage of the mission’s air-launched Pegasus XL rocket.