The launch of NASA’s next Mars rover has been delayed to no earlier than July 22 due to a contamination issue with ground support equipment, the space agency said today (June 24).

NASA’s Mars rover Perseverance was scheduled to launch toward the Red Planet on July 20 from a pad at the Cape Canaveral Air Force Station in Florida. But a problem cropped up as engineers worked to encapsulate the rover in the nosecone of its Atlas V rocket, which was built by United Launch Alliance.