Stats: Atlas 5 and Delta 4 histories and backlogs (updated April 20)

Relativity Space, a small launch startup aiming to fly its orbital rocket from Cape Canaveral for the first time next year, announced Wednesday it has signed a contract with Iridium for up to six launches of the company’s spare communications satellites. Relativity also announced it plans to develop a second launch pad at Vandenberg Air Force Base in California to allow for missions to polar orbits.

Track the progress of the launch and landing of SpaceX’s upgraded Falcon 9 rocket carrying 11 Orbcomm message relay satellites with this timeline of major events in the flight sequence.

Video highlights of the 50th Atlas 5 flight. The United Launch Alliance rocket carried the eighth Global Positioning System (GPS 2F-8) satellite for the U.S. Air Force.