Astronauts and space tourists could one day be sharing an armrest as they hurtle toward outer space under an agreement announced September 15 between aerospace giant Boeing Company and a private spaceflight marketing firm.

Under the deal, Space Adventures of Vienna, Va., will market passenger seats aboard the seven-person spaceship that Boeing is developing in Huntington Beach, Calif. It is designed to fly atop a variety of launch vehicles and is expected to be ready to go by 2015.

The spaceship, dubbed the Crew Space Transportation-100, is considered a contender for the job of ferrying astronauts to and from the International Space Station after the space shuttle program ends in 2011. If NASA chooses Boeing's spaceship for the job, Space Adventures will sell the open seats on the flights to people who can afford what will probably be an out-of-this-world price.