— SpaceX recently acquired NASA funding to put astronauts into space in 3 years.
— On Saturday, company founder Elon Musk announced that he wants to put a man on Mars within 20 years.
— Once NASA's shuttle fleet is retired this year, it is hoped private enterprise will fill the human spaceflight gap.
Private US company SpaceX hopes to put an astronaut on Mars within 10 to 20 years, the head of the firm said.
"We'll probably put a first man in space in about three years," Elon Musk told the Wall Street Journal Saturday. "We're going all the way to Mars, I think... best case 10 years, worst case 15 to 20 years."
SpaceX is one of the two leading private space companies in the United States and has won $75 million from the US space agency NASA to help its pursuit of developing a spacecraft to replace the space shuttle.
The California-based company last year completed its first successful test of an unmanned space capsule into orbit and back.
"Our goal is to facilitate the transfer of people and cargo to other planets, and then it will be up to people if they want to go," said Musk, who also runs the Tesla company which develops electric cars.
The US space shuttle program is winding down later this year with final flights of Endeavour set for next week and Atlantis in June, ending an era of American spaceflight that began with the first space shuttle mission in 1981.
When the shuttle program ends, the United States hopes private industry will be able to fill the gap by creating the next generation of spacecraft to transport astronauts into space.
"A future where humanity is out there exploring stars is an incredibly exciting future, and inspiring, and that's what we're trying to help make happen," Musk added in the interview.
Earlier this month SpaceX unveiled what Musk has called the world's most powerful rocket, the Falcon Heavy, which will have its first demonstration flight at the end of 2012.
The launcher is designed to lift into orbit satellites or spacecraft weighing more than 53 metric tons, or 117,000 pounds — more than twice the capacity of the Space Shuttle or Delta IV Heavy launcher.
SpaceX, short for Space Exploration Technologies Corporation, is one of two private companies that NASA has contracted to transport cargo to the International Space Station.
Musk, a South African who made his fortune in the Internet, created SpaceX in 2002.