Marcelo Gleiser

On Tuesday, Elon Musk's SpaceX successfully launched its most ambitious rocket to date, the Falcon Heavy.

This is a transformative spacecraft, a behemoth that essentially straps three Falcon 9 rocket cores together. At 224-feet tall, it's smaller than NASA's giant Saturn V (363 feet) — but it is the largest privately built spacecraft to date. The Falcon Heavy is capable of lifting 70 tons of payload to low-Earth orbit and almost 30 tons to a geostationary transfer orbit.