SpaceX launched what has been a top secret mission just before dusk on Sunday, not releasing the contents of its payload and changing its original mission name.

At 5:28 p.m. SpaceX launched the Optus-X satellite for Australian telecommunication company, Optus. The rocket lifted off from Kennedy Space Center's Pad 39A, traveling on a due east trajectory. With clouds in the area, most on the Space Coast only saw a short glow before the rocket disappeared.

While neither company has released details, an advisory by the Federal Aviation Administration (FAA) shows that the Optus-X satellite is set to liftoff atop a Falcon 9 during a window open from from 4:29-6:57 p.m. EST. The launch will be from Cape Canaveral Space Launch Complex 40, and travel on a due-east trajectory.

SpaceX executed a Sunday evening launch from Kennedy Space Center with a Monday launch attempt from Cape Canaveral on tap. First up was a Falcon 9 rocket from KSC’s Launch Pad 39-A on the Optux X/TD7 mission to launch a geostationary communication satellite built by Northrop Grumman for the Australian company Optus at 5:28 p.