Fancy a day’s outing skimming above the moon’s surface in a private two-person spaceship? If you’re staying at a future space hotel planned by Virgin Galactic, that may be an option.

In a speech to Virgin Galactic customers on September 27, the company’s founder, Sir Richard Branson, outlined these plans and more for the future of his commercial space fleet. “Using small, purpose-built, two-man spaceships based at space hotels our guests will be able to take breathtaking day trips programmed to fly a couple of hundred feet above of the moon’s surface,” Branson said. “They will be able to take in with their own eyes awe-inspiring views of mountains, craters and vast dry seas below.”

The plans are certainly audacious for a company that has yet to fly a customer to space. Still, more than 500 people have already paid deposits toward the $200,000 trips soon to be offered aboard Virgin Galactic’s SpaceShipTwo vehicle. These journeys will reach a peak altitude of 110 kilometers—just over the 100-kilometer height considered to mark the beginning of space—and will be suborbital flights, which return to the ground before making a full orbit of Earth.

To realize the space hotels and moon jaunts Branson foresees, he will need to develop a ride to Earth orbit, which is a whole different ball game. Attaining orbit requires speeds significantly higher than SpaceShipTwo can accomplish, and the journey brings with it attendant rises in risk, cost and technical complexity. “Where is he going to get the funding—and more importantly, how is he going to get to orbit?” asks space policy expert Roger Handberg of the University of Central Florida. “I think Branson is a dreamer and they need those still, but I don’t know that his dream is built on any realistic plan.”

Virgin Galactic has announced intentions to develop an orbital vehicle called LauncherOne. It builds on the technology of SpaceShipTwo, which launches in midair from beneath a huge mothership called WhiteKnightTwo. LauncherOne is designed to reach space for much less than the tens or hundreds of millions of dollars a typical launch costs now. “In the future, we expect to be able to launch as many as 100 new small satellites in a 24-hour period,” Branson said.

If Virgin Galactic can find an affordable way to reach orbit, the rest of its plans are feasible, experts say. “Getting something from orbit to the moon or from orbit to another orbit is a relatively simple problem once you solve that initial problem,” says former astronaut Michael Lopez-Alegria, president of the Commercial Spaceflight Federation, an industry group.

Branson isn’t alone in planning space tourism destinations. The commercial space firm Bigelow Aerospace is developing inflatable space habitats that could be used as space hotels, and has teamed with rocket-maker Space Exploration Technologies Corp. (SpaceX), which already has a launch vehicle, the Falcon 9, to reach orbit. SpaceX has flown several Falcon 9s to space, but none have carried people yet. Nevertheless, the firm is betting that tourists will line up once it starts offering passage using the booster.

Still, for any of these endeavors to succeed, space vacations will have to be not just technically possible but affordable (and most companies haven’t specified yet what price level they consider “affordable”). Further, whereas suborbital flight requires a minimum of training and physical strain, orbital flight is more grueling to passengers, usually necessitating at least six months of preparation and high levels of fitness to handle the extra G forces of launch and reentry. “I just don’t see that many multimillionaires who are physically capable of surviving such a flight,” Handberg says. “That’s the inherent limitation.”

Despite the challenges, Branson and other commercial space titans are bullish. Not content to stay in Earth orbit, Virgin Galactic, like SpaceX, is already planning on eventual trips to deep space. “In time we hope to launch missions to Mars and beyond,” Branson said in his speech. So think twice before blowing your life savings on a flyby of the moon—you might want to wait for a ride to the Red Planet.