Photos: Atlas 5 launches SBIRS GEO Flight 3

A Chinese rocket measuring around 100 feet long that launched earlier this month will likely plunge back into Earth’s atmosphere some time Monday, becoming the most massive object in decades to fall out of orbit in an uncontrolled manner.

The 330-foot tall mobile service tower is rolled away from the United Launch Alliance Delta 4 rocket at Cape Canaveral’s pad 37B in the hours before the scheduled liftoff on Dec. 7 at 6:53 p.m. EST (2353 GMT).

SpaceX chief executive Elon Musk released the first images of his company’s Falcon Heavy rocket Wednesday, showing the massive triple-core booster almost fully assembled inside its hangar at the Kennedy Space Center’s pad 39A, where it is scheduled to lift off some time in January.