Original URL: http://www.theregister.co.uk/2010/03/22/pandora_endor_corot_9b/

Pandora plus Endor: Multi hab-moon motherworld discovered

Ewok v Na'vi space wars at faraway giant planet?

By Lewis Page

Posted in Science, 22nd March 2010 11:37 GMT

Vids Top astro boffins have announced the discovery of the first planet which could be the real-life parent world of fictional habitable moons Pandora and Endor. According to Blighty's top exomoonologist, there might even be more than one inhabited moon circling the newly discovered gas giant.

Corot-9b orbits a G3 star not unlike our own sun, lying some 460 parsecs off in the constellation Serpens Cauda. The new world is reckoned to be very similar in size and makeup to the biggest planets in our star system, Jupiter and Saturn. Scanning it in detail is possible because its orbit takes it in front of its sun as viewed from Earth, making it easy to learn things about it.

Investigating boffins have been probing the far-flung giant planet since April 2008 using the COROT (COnvection ROtation and planetary Transits) space telescope in orbit above Earth. They believe that, like Jupiter and Saturn, it is a gas giant planet made up largely of hydrogen and helium.

The interesting thing about Corot-9b, however - as compared to other such planets glimpsed so far across the vasty voids of interstellar space - is that it lies at such a distance from its parent sun that liquid water could perhaps exist in its vicinity. An international team of scientists has calculated that temperatures at the planetary "gaseous surface" are "expected to be between 160 degrees and minus 20 degrees Celsius", according to Dr Henri Boffin of the European Southern Observatory. The ESO's groundbased instruments also contributed to the research.

Corot-9b 'a very exciting place for moon-dweller hunters'

While life along Earthly lines would be highly unlikely to appear on a planet such as Corot-9b, there's a more than sporting chance that it has large moons as Jupiter and Saturn do. The Saturnian moon Titan even has an atmosphere denser than ours, though this is made up of straight nitrogen with clouds of methane and patio-gas, rather than nitrox-mix air with added water in various forms as we have here.

But a large moon of Corot-9b could have a nice warm atmosphere with liquid water on the surface - the same conditions in which life arose on Earth. Such a moon might be home to an alien carbon-based biosphere, perhaps even including intelligent natives - as in the stories of the extrasolar moons Pandora and Endor.

We got in touch with Blighty's top exomoonologist, Dave Kipping of University College London, to find out what the chances were of finding blue pigtail-brainplug dragonriders or small, irritating, homicidal teddybears out in the Corot-9 system.

"CoRoT-9 is a very exciting system for exomoon hunters," confirmed Kipping. "Moons as large as the Earth could not only be dynamically stable but also detectable with the CoRoT spacecraft."

But what about the aliens?

Call SETI and tell them to swing the Allen Array round!

The exomoon expert seems cautiously hopeful:

"In terms of life, moons residing in the habitable-zone of their star are exciting candidates," he says. "However, so far we have only seen life appear on one body, the Earth. We cannot really say how likely it is that life, let alone intelligence, would evolve in individual systems.

"Having said that, I would not be surprised if SETI [the Search for ExtraTerrestrial Intelligence] add CoRoT-9 to their list of priority systems and start listening for signals."

Of course, both Jupiter and Saturn have many moons, not just one like Earth: the two mega-planets are the centres, almost, of small pocket star systems.

If Corot-9b were similarly well-endowed with moons, they would all be potentially habitable. This raises the intriguing prospect of multiple inhabited moons - either home to separately-evolved life, or alternatively due to life spreading from one moon to another.

If intelligent life did arise in such circumstances, the presence of other habitable worlds nearby would surely be a terrific spur to the development of space travel. Intermoon voyages would be far easier than interplanetary or interstellar ones, too.

Even where only one moon originally had life, it seems at least feasible that soon others would be seeded and then colonised until Corot-9b had several inhabited worlds in orbit about it, conducting space trade - perhaps even space wars - with one another.

We asked Kipping to comment on the likelihood that even now intermoon conflict may be seeing Ewok or Na'vi space battlefleets locked in mortal combat off the roiling atmospheric deeps of Corot-9b. Sadly, he remained pretty noncommittal.

"At this point, all we know is that a habitable moon is a plausible possibility. I would expect a single large moon to be stable but whether a whole system of moons is possible remains an unanswered question right now," he says.

Even so, if we were the boss of SETI we'd be focusing the Allen Telescope Array on Corot-9 toot sweet.

For those with enough brains to handle it, the Corot-9b research is now published in hefty boffinry mag Nature. You can also read it free here in pdf, courtesy of the ESO's Dr Boffin. ®