SpaceX, Northrop seek to break launch gremlin curse with Friday night attempts

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  A Falcon 9 rocket is ready to go on Friday ahead of an evening launch attempt. [credit: Trevor Mahlmann for Ars ]

SpaceX has a big launch on tap for this evening, delivering a valuable satellite into orbit for the US Space Force. With a liftoff time of 9:43pm ET (01:43 UTC Saturday), the company's Falcon 9 rocket is due to deliver a fourth GPS III satellite into geostationary transfer orbit. Weather conditions look good, with a 70-percent chance of "go" conditions.

Built by Lockheed Martin, the GPS III satellites were designed to modernize the current Global Positioning System constellation, providing three-times greater accuracy and improved anti-jamming capabilities. This mission will launch on a new Falcon 9 first stage, but SpaceX and the Space Force have reached an agreement that will allow future GPS missions to launch on flight-proven rockets.

While the payload is important, perhaps more intriguing this evening in Florida will be whether this mission actually gets off the launch pad. The last week has seen a succession of US launch attempts canceled for issues primarily related to ground systems.