Atlas V on SLC-41 after being scrubbed due to an unexpected system response from remotely commanded ground-system liquid-oxygen valves. [credit: Trevor Mahlmann for Ars ]
Update 6:15pm EST: A ground-systems issue got United Launch Alliance again. Prior to the opening of the Atlas V launch window on Wednesday evening, an issue related to ground-system liquid-oxygen valves could not be solved in time for a launch attempt from Florida.
The company will now stand down for 48 hours to address the issue, which would allow for SpaceX to attempt a launch of a GPS III satellite for the Space Force on Thursday.
Original post 11:25am EST: United Launch Alliance returns to one of its two main pads at Cape Canaveral Air Force Station Wednesday to try to break a string of recent launch scrubs due to various issues, mostly related to ground systems.