SpaceX's Falcon Heavy lifted off into space from the Kennedy Space Center, Florida, yesterday, though NASA was not involved in the launch.
''It seems surreal to me,'' Musk said during a news conference after the launch.
According to experts, the launch of the turbocharged version of the workhorse Falcon 9 rocket, which has been carrying cargo to space for years, marks an important milestone in spaceflight. It is the first launch of a powerful rocket by a private company rather than a government space agency.
The rocket carried an unusual payload - Musk's red Roadster, an electric sports car produced by Tesla, with a mannequin wearing one of SpaceX's spacesuits strapped inside the vehicle. They are expected to orbit the sun for hundreds of millions of years.
''It's kind of silly and fun, but silly and fun things are important,'' Musk said.
According to commentators, the success would inspire SpaceX to develop even larger rockets, which could help fulfill Musk's dream of sending people to Mars. For the Mars mission Musk has planned a new-generation rocket called BFR. (the B stands for big; the R for rocket) to be ready for launch in the mid-2020s.
Musk had concerns the experimental 23-story rocket might explode with the force of 4 million pounds' worth of TNT, but the Falcon Heavy successfully cleared launch pad 39A at Kennedy Space Center.
Falcon Heavy's successful blast-off, a system that will cost about $90 million per launch is expected to disrupt the industry.
"It means we're able to offer heavy-lift... for not much more than the cost of a Falcon 9," Musk told reporters on Monday, referring to SpaceX's $62-million single-booster rocket. "If we're successful in this, it is game over for all other heavy-lift rockets."