Photos: America’s 100th EELV blasts off

Follow the key events of the Soyuz rocket’s ascent into orbit from the Guiana Space Center with the SES 15 communications satellite.

The next flight of United Launch Alliance’s triple-barrel Delta 4-Heavy rocket has been delayed from June to late August, military officials said Friday.

A steel tube built as a stand-in for the core stage of NASA’s Space Launch System has arrived at the Kennedy Space Center for a series of rehearsals to hone the skills of technicians before the real rocket reaches the spaceport, an oft-delayed milestone that could still be a year or more away.