Atlas 5 launch as seen from the KSC Press Site (members only)

An Iranian Simorgh rocket launch carrying an Earth observation spacecraft faltered before reaching orbit Tuesday after analysts used imagery from commercial U.S. satellites in recent weeks to track preparations for the mission.

SpaceX’s Falcon 9 rocket ignited its main engines at Cape Canaveral’s Complex 40 launch pad Thursday night, clearing a major hurdle before liftoff May 31 with the SES 12 communications satellite.

Calling on the Atlas 5 rocket to flex its muscles one more time, Orbital ATK will partner with United Launch Alliance once again to send a massive load of supplies to the International Space Station astronauts early next year.