LOS ANGELES — A Russian rocket carrying an experimental inflatable spacecraft blasted off yesterday on a mission to explore the possibility of building a commercial space station, officials said.

The Genesis I spacecraft lifted off at 6:53 p.m. Moscow time aboard a converted Cold War ballistic missile from the southern Ural Mountains, according to the Russian strategic missile forces.

It was not immediately known whether Genesis reached its designated orbit about 340 miles above Earth.

Genesis I marked the first launch for Bigelow Aerospace, a startup founded by Las Vegas real estate mogul Robert Bigelow, who is trying to break into the fledgling commercial spaceflight business.

Mr. Bigelow, who owns the Budget Suites of America hotel chain, envisions building a private orbiting space complex by 2015 that will be made up of several expandable Genesis-like modules linked together.

The entrepreneur, who has committed $500 million toward the project, said the outpost could be used as a space hotel, science lab, or college.

The goal of the Genesis mission is to test inflatable technology and determine how well the process works in orbit. Future launches will test docking among several spacecraft.

The watermelon-shaped Genesis I is a one-third scale prototype of a commercial space station to which the company eventually hopes to fly humans. Equipped with a dozen cameras to shoot video and photos of the Earth, the spacecraft is supposed to circle the planet for at least five years while scientists study its durability.

The spacecraft measured 14 feet long and 4 feet wide at launch and was to inflate to twice that width in space. It carried insects and photos of Bigelow employees, and scientists planned to study the former to determine how well the critters survive the flight.

Because the mission was experimental, Mr. Bigelow said he was prepared for possible spacecraft failure.

“I wouldn’t be the least bit surprised if we have a number of different systems fail,” he said Tuesday. “I would hope that we have some success.”

In the 1990s, NASA studied inflatable technology for a possible trip to Mars, but later dropped the idea after determining the inflatable modules were too expensive. Bigelow Aerospace plans another launch in the fall of its Genesis II spacecraft, which will carry mementos from the public for $295 apiece. Over the next several years, the company plans to test larger prototype spacecraft, including a full-scale mockup slated to launch in 2012.