British tycoon Richard Branson, whose company is launching a space tourism programme, on Sunday hailed the late US astronaut Neil Armstrong as "an extraordinary individual".
Branson, 62, said he felt privileged to have met the first man on the moon, whose death was confirmed by family members on Saturday.
"He was an extraordinary individual who had achieved an absolutely extraordinary thing in his lifetime," the billionaire told Britain's Sky News television from Necker Island, his private isle in the Caribbean.
"He will inspire generations for years to come," Branson added.
"He was quite a shy, quiet individual, and a family man. Ever since the moon landing I think people have seen very little of him, so it was a great privilege to actually spend a little bit of time with him.
"He made quite sure that he stayed very grounded when he came back to earth."
Some 500 million people watched on television as Armstrong made his first steps onto the moon's surface in July 1969.
He died aged 82 from complications following cardiac bypass surgery.
Branson said Armstrong believed humans would eventually colonise other planets, and was convinced that "within the next 30 years we will have set up a base on Mars".
He added that he had last seen the Apollo 11 commander at a memorial service for fellow adventurer Steve Fossett, who disappeared in 2007 while on a solo flight in Nevada.
Armstrong had been "excited by the idea that private money was going into space", Branson said. "He dearly wanted to see the investment in space travel continuing."
Branson's company Virgin Galactic is due to launch its space tourism programme in late 2013 or early 2014.
More than 500 people—including actor Ashton Kutcher and scientist Stephen Hawking—have signed up for the 60-mile (100-kilometre), two-hour ride into space, at a cost of £128,000 ($200,000, 162,000 euros) each.
Branson announced last month that he and his two adult children would be aboard the first flight.
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