Nasa: Is there signal on Mars?

In what may be the ultimate in long-distance telephone services, Nasa has put out a call for a commercially owned and operated satellite network - on Mars.

The US space agency needs to keep in touch with its rovers, landers and orbiters that have been chipping away at studies and experiments to learn if the planet most like Earth in the solar system ever supported life.

The probes, however, are useless if they cannot relay their results, and the two communication satellites currently in orbit are getting old. The Mars Odyssey craft was launched in 2001, while the Mars Reconnaissance Orbiter followed in 2005.

A commercially operated communications service could be less expensive and more capable than what Nasa could build and operate on its own, while providing "appropriate return-on-investment" to the service provider, Nasa Mars exploration programme executive Lisa May said in a statement.

For now, Nasa is just seeking ideas, with no firm plans or funding to purchase commercial communication services on Mars. Proposals are due by 25 August.

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