As the asteroid 2012 DA14 skims just 28,000km above our heads today, many eyes will be turned skywards.
But for one group of far-sighted multimillionaires, their interest is of the vested variety. The almost 50 metre wide space rock rattling past our planet could be worth some US$1.5 trillion (Dh5.5tn).
That is why ultra-wealthy A-listers including Larry Page, the Google chief executive, his executive chairman Eric Schmidt, the Texas billionaire Ross Perot Jr and the spacefaring software executive Charles Simonyi are backing a US company that plans to commercially mine such rich cosmic seams.
What Planetary Resources is after are high-value materials locked in asteroids - such as platinum, palladium and other rare metals.
The company says it is the possibility of securing thousands of tonnes of such solar gold dust that has spurred the serious financial heft from his backers - although they are reluctant to divulge the amounts they have put in. Still, to add a little star quality to the list, the sci-fi film director James Cameron has signed on as a senior adviser.
But securing huge amounts of precious metals does throw up a paradox: if the value of these elements is high because of their rarity, surely flooding the market with tonnes of it will cause that value to plummet - making the financial viability of space mining difficult to square.
"The question is, how does the economics come into this?" says Adam Bruckner, a professor of aeronautics and astronautics at the University of Washington. "Can it ultimately be less expensive to find [PGMs] on an asteroid than on Earth?" But he concedes, "At some point in the future - and it's debatable how far in the future - the two lines will cross."
Chris Lewicki, Planetary Resources' president, is unfazed. "What will settle the winners from the laggards will be who can find the best economic model," he says.
Eric Anderson, the company co-chairman who is also an aerospace engineer and pioneer in the commercial space-flight industry, points to more Earth-bound examples. Developing deep-sea oilfields off the coast of Brazil is expected to cost billions before the first barrel is pumped, he says, which makes the "single-digit billions" he estimates his company will need to launch a prospecting ship and return within the next decade a less daunting number.
"These are on the scale of the kind of resource dollars that get spent on Earth to bring something on line," Mr Anderson says. "The private equity markets are used to that."
But even failure can pay off. Fourteen years ago, a company called SpaceDev planned to take on a commercial deep-space mission to an asteroid. It eventually abandoned the idea and turned its attention instead to the development of small satellites and hybrid rocket engines. In 2008, the company was acquired by Sierra Nevada, which is currently receiving millions of dollars from Nasa for spaceship development.
Planetary Resources does not intend to wait for doubt to stall the project. "We're launching the first telescopes [to identify suitable asteroids] in 18 months, and we're actually building them ourselves in our own facility," Mr Lewicki told NewScientist.com recently.
"We have a team of more than 30 engineers with long experience of doing this kind of thing at Nasa's jet propulsion laboratory, myself included. Many of our team worked on designing and building Nasa's Curiosity [Mars] rover, and I was a system engineer on the Spirit and Opportunity rovers and flight director when we landed them on Mars."
Mr Anderson wants Planetary Resources "to be the first to harness potentially trillions of dollars of minerals including platinum group metals [PGMs] by using robotic technology to mine asteroids", he says, adding while the company, based in Seattle, has "enough funding for several years of operations, including its initial prospecting missions, [he] would consider an initial public offering for future financing needs".
"I would love to take the company public someday.
"I think it's really important for the public to have a chance to be part of this, but not until we're ready. We need to fly to space first," he says.
Mr Anderson, whose company Space Adventures has helped millionaires and billionaires go on 10-day trips to the International Space Station, founded Planetary Resources with Peter Diamandis, the man behind the multimillion-dollar X Prize programme, the Rocket Racing League and the Zero G weightless-aircraft tourist venture.
Mr Anderson and Mr Diamandis serve as co-chairmen of the venture they founded.
So how does an asteroid such as DA14 come with a price tag of $1.5tn?
Some near-Earth asteroids contain PGMs, ruthenium, rhodium, palladium, osmium, iridium and platinum, in much higher concentrations than on Earth. In space, Planetary Resources says, a single PGMs-rich 500 metre wide asteroid contains about 1.5 times the known world-reserves of PGMs, which stood at 2,125 million troy ounces in 2010. Assuming DA14 is just such an asteroid, albeit it 10 times smaller, at this month's current average combined spot prices for PGMs of $4,763 per troy ounce, it could yield a return of more than $1.51 trillion.
And really, $1.51 trillion is not bad for a relative speck of space dust.
Platinum climbed for a third day yesterday. Platinum for immediate delivery gained as much as 0.7 per cent to $1,733.25 an ounce and was at $1,729.12 in afternoon trading in Singapore. The spread between the two metals widened to as much as $88.75 in intraday trading, the most since August 2011, according to data compiled by Bloomberg.
Platinum has climbed 12 per cent this year, while gold lost 1.8 per cent. "It's supply concern that's driving platinum," says Gavin Wendt, a director at Mine Life. "There's enough news to keep driving the platinum price higher."
Platinum production will drop 2.7 per cent to 5.68 million ounces this year, the least since 2000, as demand from car makers, for vehicle exhaust catalytic converters, increases 0.5 per cent, Barclays estimates. So it seems well worth scouring the skies for other sources.
There are more than 1,500 asteroids that are as easy to get to as the surface of the Moon, Planetary Resources claims and, unlike Earth, where heavier metals are closer to the core, metals in asteroids are distributed throughout their body, making them easier to extract.
Part of the company's early-phase business plan is to strike a deal with Nasa. "Nasa is conducting analyses of the best asteroids for a human asteroid mission in 2025," Mr Lewicki says.
"Although Nasa's requirements for a human mission are different than Planetary Resources' requirements for a robotic mission, there is synergy between Nasa and Planetary Resources in asteroid selection. Asteroids characterised and explored by Planetary Resources during prospecting missions may also help Nasa characterise potential human-mission targets.
"Three, four, five years out, depending on trajectory, is when we envision getting up close and personal with an asteroid," says Mr Lewicki.
As for the sceptics, Mr Lewicki points out: "Everything is science fiction - right up to the point that it's science fact."
* with agencies