IT WILL be one near miss for man, but a new breed of space entrepreneurs hope it will presage one giant leap for mankind.
When asteroid 2012-DA14 hurtles past Earth later this month in the closest of cosmic calls, US government scientists will be closely tracking its path from NASA's observatory in the Californian desert. Not least thanks to the attention of Hollywood, the world's interest in asteroid fly-bys has until now been focused on the danger of a cataclysmic collision.
Record setting asteroid fly-by
In February, an asteroid will fly past Earth closer than many man-made satellites. It will be the first time astronomers have seen an object so big come so close to our planet.
But for aspiring asteroid miners, the lump of debris the size of a school gymnasium that will pass at 28,800km/h within 27,520 kilometres - closer than many of the satellites circling the planet - symbolises a commercial opening on the final frontier.
It may sound more like science fiction than reality, but two US companies have been outlining plans to harvest asteroids for mineral wealth in what they hope will be a 21st century equivalent of gold and oil rushes.
They intend to deploy small satellites to prospect asteroids, then effectively lasso them, transporting them into Earth's orbit to harvest precious metals and liquids.
The newest entrant to the fast-developing asteroid mining world is Deep Space Industries, which has just unveiled ambitious plans to send prospecting spacecraft in two years' time and begin extraction by 2020.
''It is exciting to be present at the beginning of the second space age, led by commercial businesses,'' Deep Space chief executive, David Gump, said. ''The biggest challenge for humanity expanding into space is the cost of launching material from the ground. If you can get the materials in space, that is a huge step towards expanding human civilisation beyond Earth.''
His company is now a competitor to Planetary Resources, which launched last year with a roster of investors that includes Larry Page, the co-founder of Google, Eric Schmidt, Google's chairman, and James Cameron, the film director and deep-sea explorer.
Led by Eric Anderson, co-founder of Space Adventures, which took seven wealthy individuals to the International Space Station, Planetary Resources plans to use miniature spacecraft-telescopes to survey asteroids. It will launch them in partnership with Sir Richard Branson's Virgin Galactic space tourism business.
Deep Space intends to rent space on larger satellites to launch three 25-kilogram mini-satellites called ''Fireflies'' in 2015 on six-month missions to take photographs for the first close-up views of asteroids.
A year later, it would dispatch 32-kilogram ''Dragonflies'' on return expeditions lasting two to four years to collect samples of material, identifying viable asteroids and bring them into Earth's orbit to start mining by 2020 using a third generation of spacecraft, the ''Harvester''.
The technology is in the early days for this most challenging stage, Mr Gump said. Deep Space expects to use a large satellite to drag an asteroid out of its orbit around the sun, and into Earth's orbit. The target asteroids would be small, maybe just 4.5 metres to 6 metres across, but if correctly identified should contain hundreds of tons of material. Extraction would focus initially on liquids that can be turned into fuel to extend the life of commercial satellites.
The companies are cagey about costs, but Deep Space is courting investors for the Fireflies phase, which it estimates will require $20 million.