VANDENBERG AIR FORCE BASE, Calif. — A Falcon 9 rocket roared into the sky on Saturday carrying 10 communications satellites — a return by SpaceX and its billionaire leader, Elon Musk, to the business of launching satellites to orbit.

But financial details disclosed this past week about the company overshadowed the successful liftoff, raising questions about the viability of Mr. Musk’s long-range plans for SpaceX and his vision of sending people to Mars.

SpaceX, based in Hawthorne, Calif., has been set back since September, when a different Falcon 9 caught fire and exploded on a launchpad in Florida, destroying the rocket and its payload, a $200 million Israeli satellite that Facebook had planned to lease to expand global internet services. The company’s rockets had been grounded since then. An internal investigation concluded that a failure of a helium vessel in the second stage liquid oxygen tank had led to the conflagration.

The Federal Aviation Administration, which regulates commercial space launches, accepted SpaceX’s report on the explosion’s causes on Jan. 6 and issued a launch license, clearing the way for Saturday’s liftoff here, on the other side of the country. To prevent a recurrence, SpaceX adjusted its fueling procedures to avoid overcooling of the helium.