Google Inc executives Larry Page and Eric Schmidt and filmmaker James Cameron are among those bankrolling a venture to survey and eventually extract precious metals and rare minerals from asteroids that orbit near Earth, the company said on Tuesday.

  Planetary Resources, based in Bellevue, Washington, initially will focus on developing and selling extremely low-cost robotic spacecraft for surveying missions.

  A demonstration mission in orbit around Earth is expected to be launched within two years, said company co-founders Peter Diamandis and Eric Anderson.

  Planetary Resources' aim is to open deep-space exploration to private industry, much like the $10 million Ansari X Prize competition, which Diamandis created.

  Planetary Resources' first customers are likely to be science agencies, such as NASA, as well as private research institutes.

  Within five to 10 years, however, the company expects to progress from selling observation platforms in orbit around Earth to prospecting services. It plans to tap some of the thousands of asteroids that pass relatively close to Earth and extract their raw materials.

  Not all missions would return precious metals and minerals to Earth. In addition to mining for platinum and other precious metals, the company plans to tap asteroids' water to supply orbiting fuel depots, which could be used by NASA and others for robotic and human space missions.

  "We have a long view. We're not expecting this company to be an overnight financial home run. This is going to take time," Anderson said.

  Planetary Resources declined to discuss specifics about how and when asteroid mining would begin. A 30-meter long (98-foot) asteroid can hold as much as $25 billion to $50 billion worth of platinum at today's prices, Diamandis said.

  The company's first step is to develop technologies to cut the cost of deep-space robotic probes to one-tenth to one-hundredth the cost of current space missions, which run hundreds of millions of dollars, Diamandis said.

  行星资源集团本周二公布了一项到近地小行星进行勘探，并最终开采贵重金属和稀有矿产的计划。谷歌公司高管拉里·佩奇和埃里克·施密特、以及著名导演詹姆斯-卡梅隆等人都加入了这项风险投资。

  这家公司的总部位于华盛顿贝尔维尤，最初将着眼于研发并出售价格极其低廉的机器人宇宙飞船，用于勘探调查任务。

  该公司联合创始人彼得-迪曼蒂斯和埃里克-安德森说，行星资源集团预计两年内在近地轨道开展首次示范任务。

  该公司的目标是在私人企业中开展外层空间勘测业务，就如同迪曼蒂斯发起的奖金高达一千万美元的安萨里X-Prize大奖赛。

  该公司的首位客户很可能是科学机构，比如美国宇航局，以及私人研究机构。

  但该公司计划在10年内将业务从出售近地轨道观测平台发展到探矿服务，并计划开发数万颗近地小行星中的一部分，开采其中的稀有矿藏。

  并非所有的任务都会带贵重金属和矿产回地球。除了开采白金和其它贵重金属外，该公司还计划开采小行星中的水资源，来供应轨道燃料补给站，美国宇航局和其它机构都可以利用这些补给站进行机器人进行的和载人的航天任务。

  安德森说：“我们目光长远。我们并不期待公司能一夜暴富。这需要时间。”

  该公司拒绝讨论有关小行星采矿如何开展、以及何时开展等细节问题。迪曼蒂斯说，按如今的价格计算，一个直径30米（98英寸）的小行星可能含有最多价值250亿美元至500亿美元的白金。

  他还表示，该公司的第一步计划是研发能够削减外层机器人探测费用的技术，将费用削减至目前高达数亿美元的航空任务成本的1/10至1/100。