SpaceX founder Elon Musk said Wednesday that his company will attempt to launch its futuristic, bullet-shaped Starship to orbit in January, but he's not betting on success for that first test flight.

"There's a lot of risk associated with this first launch, so I would not say that it is likely to be successful, but we'll make a lot of progress," he said during a virtual meeting organized by the National Academy of Sciences.

Musk said he's confident Starship—launching for the first time atop a mega booster—will successfully reach orbit sometime in 2022. After a dozen or so orbital test flights next year, SpaceX then would start launching valuable satellites and other payloads to orbit on Starships in 2023, he said.

NASA has contracted with SpaceX to use Starship for delivering astronauts to the lunar surface as early as 2025. Musk plans to use the reusable ships to eventually land people on Mars.

The shiny, stainless steel Starship and its first-stage booster—called the Super Heavy—will be the biggest rocket ever to fly, towering 394 feet (120 meters). Liftoff thrust, Musk noted, will be more than double that of NASA's Saturn V rockets that carried astronauts to the moon a half-century ago.