The belated launch of a powerful Earth-imaging satellite that will take the highest resolution pictures in the market, postponed by an unprecedented wildfire near the pad, is scheduled to fly on Friday.

The 32-story-tall mobile service tower at the Delta 4’s launch pad at Vandenberg Air Force Base in California was retracted away from the rocket Thursday in advance of a planned liftoff with a top secret National Reconnaissance Office payload.

SpaceX’s next Falcon 9 rocket arrived at Kennedy Space Center’s pad 39A on Thursday for a hold-down engine firing ahead of launch next week with the U.S. Air Force’s X-37B spaceplane. The brief engine ignition occurred at 4:30 p.m. EDT (2030 GMT).