The Space Adventures orbital spaceflight program is the only way for non-astronauts to visit the International Space Station ( ISS). Now, Space Adventures had brokered a deal that increases the number of spaceflight participants.

At a press conference today, Eric Anderson, Space Adventures president and CEO, announced that his company will be providing private missions to the ISS, rather than partnering with the Russian Space Agency.

Anderson said, “We’re here to open the frontier.”

This move frees up the seat on the Soyuz rocket usually given to a cosmonaut or astronaut. Now two passengers will be able to travel together, rather than one passenger visiting the ISS alone.

Space adventurers will fly to the ISS in a specially designed Soyuz rocket, piloted by a cosmonaut. Anderson says production of the Soyuz rockets will increase from two to four a year.

According to Alexey B. Krasnov of the Roskosmos, “This private mission, flying two Space Adventures’ clients at once, will not interfere with the implementation of the ISS program or the obligations of the Russian space agency; on the contrary, it shall add flexibility and redundancy to our ISS transportation capabilities.” (Of course, it also doubles Space Adventure’s income.)

Anderson believes that orbital tourism will pave the way for tourist missions to the moon. “We’re no longer a space tourism company. We’re a space mission company.company.... We look forward to pioneering the future.”

Their first mission will take place in the latter half of 2011.