Photos: Atlas 5 on the pad for X-37B launch

United Launch Alliance has completed stacking of the major elements of the Atlas 5 rocket assigned to power NASA’s Perseverance rover toward Mars, but the mission’s launch date has been pushed back three days to July 20 after teams repaired an issue with a crane in the Atlas 5’s assembly building.

The Atlas rocket to launch four formation-flying spacecraft for NASA in March began to take shape Wednesday at the assembly building adjacent to the Complex 41 pad.

Launching the Wideband Global SATCOM 8 satellite for the U.S. military, a United Launch Alliance Delta 4 rocket thundered away from Cape Canaveral at 6:53 p.m. EST (2353 GMT).