NASA’s next Mars mission has now burned nearly half of its launch window

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  The United Launch Alliance Atlas V rocket at Cape Canaveral Air Force Station undergoes a Wet Dress Rehearsal in preparation for launching Mars Perseverance. [credit: United Launch Alliance ]

NASA says it will be forced to delay the launch of its multibillion-dollar Perseverance mission to no earlier than July 30. The Mars-bound large rover must launch on an Atlas V rocket from Cape Canaveral Air Force Station in Florida before the middle of August, or it will miss Earth's conjunction with the red planet.

This is the third delay in the launch campaign for Perseverance, formerly known as Mars 2020, and the most concerning because a new, formal launch date has not been set.

A problem arose during a Wet Dress Rehearsal test earlier this month. During this standard prelaunch test, an Atlas V rocket is fueled with propellant and a countdown is conducted until the final moments before ignition. So what happened? "A liquid-oxygen sensor line presented off-nominal data during the Wet Dress Rehearsal, and additional time is needed for the team to inspect and evaluate," NASA said in a statement on Tuesday afternoon, in response to a query from Ars.