Two members of the public are set to take an historic trip around the Moon, according to an announcement from SpaceX CEO Elon Musk. As The Verge reports, the anonymous private citizens have already placed substantial deposits on the commercial space flight.

The private spacecraft company SpaceX revealed on Monday that the Falcon Heavy rocket will be launching with its Crew Dragon spacecraft in late 2018. The mission will consist of a circumnavigation of the Moon, passing over the body’s surface before traveling farther into space and returning to Earth. In total, the trip will cover 300,000 to 400,000 miles and take a week to complete.

A noteworthy part of the plan is the human cargo that will be on board. Instead of professional astronauts, the craft will carry two paying customers into space. The passengers, who’ve yet to be named, will both need to pass several fitness tests before they're permitted to make the journey. According to The Verge, Musk said the customers are “very serious” and that the cost of the trip is “comparable” to that of a crewed mission to the International Space Station. The goal for SpaceX is to eventually send one or two commercial flights into space each year, which could account for 10 to 20 percent of the company’s earnings.

[h/t The Verge]