SpaceX, which has flown unmanned cargo capsules to the International Space Station, planned to unveil a new spacecraft Thursday designed to ferry astronauts to low-Earth orbit.
The Southern California-based rocket builder, founded by billionaire Elon Musk, is one of several private companies vying to develop "space taxis" for NASA to replace the retired space shuttle fleet.
The reveal will take place at SpaceX's headquarters near Los Angeles International Airport.
In a NASA briefing with reporters last year, Musk said the manned version would look futuristic like an "alien spaceship" with side-mounted thrusters, landings legs that pop out and large windows for astronauts to marvel at Earth's curvature.
"It's going to be cool," Musk said at the time.
Since the shuttle fleet retired in 2011, NASA has depended on Russian rockets to transport astronauts to orbit and back, paying nearly $71 million per seat. The space agency has said it wants U.S. companies to fill the void by 2017 and has doled out seed money to spur innovation.
SpaceX -- short for Space Exploration Technologies Corp. -- has made four cargo runs to the giant orbiting outpost some 200 miles above Earth. Just last month, its Dragon capsule splashed into the Pacific, returning nearly 2 tons of science experiments and old equipment.
Companies competing for the right to ferry station astronauts need to design a spacecraft that can seat a crew of seven and be equipped with life support systems and an escape hatch in case of emergency.
SpaceX and longtime NASA contractor Boeing Co. are "more or less neck and neck" in the competition, but there's a long way to go before astronauts can rocket out of the atmosphere on private spacecraft, said John Logsdon, professor emeritus of political science and international affairs at George Washington University.
Logsdon said progress by private companies is slower than anticipated mainly because Congress has not fully funded NASA's budget request for the effort. He said it's important for the U.S. to wean its reliance on Russia given the political tension over the annexation of Crimea.
"It's essential to have our own capability to transport people to space," he said. "This is an important step in that direction."