SAN FRANCISCO (Diya TV) — SpaceX plans to send two people on an orbit around the Moon, the company’s chief executive Elon Musk announced Monday.

It will be a private mission for two paying customers, not NASA astronauts, who approached the company themselves. The passengers have already paid a “significant deposit,” Musk said.

The trip around the Moon will take approximately one week, skimming the surface of the astronomical body, moving a bit further into deep space before finally looping back to Earth. In total, the two passengers will travel between 300,000 and 400,000 miles. SpaceX plans to execute the trip during the second quarter of 2018 on its Crew Dragon spacecraft with the Falcon Heavy rocket, which is scheduled to make its maiden launch this summer.

However, Musk, known for setting more than one unrealistic deadline, promised the public back in 2011 to have civilians traveling to outer space within three years.

The two passengers, whose names weren’t revealed, already know each other and will begin training for the mission later this year. Musk declined to provide specific details on the cost of the mission, but said it was “comparable” or a little more than the cost of a crewed mission to the International Space Station.

One ticket on the Russian Soyuz rocket runs NASA $80 million.

Musk believes these private missions could be a “significant driver of revenue” for the company and expects to have at least one or two a year, possibly making up 10 to 20 percent of SpaceX revenue.

A permit from the United Nations will not be necessary, according to Musk, though the trip will need to be licensed by the Federal Aviation Administration.

The Crew Dragon, a craft which is yet to make its maiden flight, is an automated vehicle. The system operates autonomously for the majority of the flight. In the event of an emergency, passengers would be required to take action, but “the success rate is quite high,” Musk said. Changes will be made to the Dragon’s communications system, mostly to allow for communication in deep space.

SpaceX has already been developing the Crew Dragon to carry people for NASA, as part of the agency’s Commercial Crew Program. It’s an initiative that tasks two private companies — SpaceX and Boeing — with developing vehicles that can carry people to and from the International Space Station.