The current draft rules for the six new contests were developed by in-house by NASA personnel, Sponberg said, adding that before the agency launches the competitions officially, feedback from those who will compete in them is vital. "The whole idea is to go out eternally and to have the people competing for this, or whoever, let us know what needs tweaking."

While the new challenges are not yet official, NASA announced a series of contests throughout 2005 that covered a broad swath of technologies that ranged from better spacesuit gloves to unmanned vehicles for lunar and planetary exploration. The program has secured $10 million for current contests and hopes for an additional $10 million to support future competitions, Sponberg said.

The space agency also held its first competition - the 2005 Beam Power and Tether Centennial Challenges - last year, in which 11 teams vied for two $50,000 prizes. Both purses went unclaimed, with even larger cash prizes promised for this year's contest, NASA officials have said.

Other challenges, such as those charging entrants to develop suborbital rockets, lunar excavators and machines to cull oxygen from mock lunar regolith, have yet start competition. The first spacesuit glove competition, a partnership with the Volanz Aerospace Inc., is set for November 2006, to be followed by the lunar excavation challenge in late 2006 or early 2007, NASA officials said.

Meanwhile, Centennial Challenge program officials are seeking new partners for the upcoming contests, Sponberg said. When new partners sign onto to a specific challenge will determine how soon the contest can begin in earnest, he added.

Here's a brief description of each of NASA's new planned challenges:

• Fuel Depot Challenge: Expected to award a $5 million prize to the first team to build, launch and demonstrate a sub-scale facility that could store or produce liquid oxygen and liquid hydrogen - used to fuel spacecraft - in Earth orbit. In November 2005, NASA chief Michael Griffin said future space missions would rely on privately built fuel stations for resupply.
• Human All-Terrain Vehicle Challenge: With NASA aiming to return astronauts to the Moon by 2017, knowing how to move humans from place to place will be imperative. This $1 million contest would challenge inventors to build human-driven rovers that are agile, easy to stow and reliable.
• Low-Cost Space Pressure Suit Challenge: Aimed at increasing the industrial base for human spaceflight and jump-starting development for commercially available spacesuits, this $500,000 competition would reward the first team to build a spacesuit that meets design and test requirements - which includes a depressurization test on an instrumented mannequin. Teams must also sell a certain number of spacesuits to demonstrate cost effectiveness.
• Lunar Night Power Source Challenge: NASA is promoting the development of power systems capable of operating for extended periods in a harsh environment. To win a $500,000 prize, innovators are expected to be the first to demonstrate a rechargeable power source that provides power over 14 days - about one lunar night- while meeting volume and heat requirements.
• Micro Reentry Vehicle Challenge: Most students have encountered the egg-drop in one way or another, but this Centennial Challenge would take it to the extreme. The planned contest would task entrants to build a vehicle that could deliver at least six of 12 common hen eggs to Earth safely - and undamaged - from low-Earth orbit. The first to do so would nab a $2 million prize. Such reentry systems could lead to a routine sample-return method from orbital space stations, NASA officials said.
• Station-Keeping Solar Sail Challenge: Aimed at promoting the development of working solar sails and exploiting novel spacecraft orbits, this challenge would offer a $2.5 million purse for each of two distinct achievements, according to its description. The first would challenge a team to be the first to successfully deploy a solar sail, demonstrate an acceleration change and fly through a designated target. The second contest would challenge competitors maintain a sail's position above or below a target area for 90 days.

Full draft rules for each the six planned challenges above can be found by clicking here. All comments must be submitted by 5:00 EDT (2100 GMT) March 27, 2006, NASA officials said.

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