The Rosetta spacecraft’s Philae lander, which touched down on comet 67P/Churyumov-Gerasimenko last year, since that time has provided astronomers with images of a body with distinct and unexpected features. Now, two scientists have put forward a surprising explanation for its properties; micro-organisms that shape cometary activity.
Data from the Rosetta spacecraft have revealed an oddly ‘duck shaped’ comet, about 4.3 by 4.1 km in size. It seems to have a black crust and underlying ice and images show large, smooth ‘seas’, flat-bottomed craters and a surface peppered with mega-boulders.
Re-frozen bodies of water overlain with organic debris comprise the crater lakes. Parallel furrows correlate to the flexing of the asymmetric and spinning double-lobed comet, which creates fractures in the ice underneath.
Dr Max Wallis, of the University of Cardiff, and Professor Chandra Wickramasinghe, Director of the Buckingham Centre for Astrobiology, maintain that all these features are consistent with a mixture of ice and organic material that consolidate under the sun’s warming during the comet’s orbiting in space, when active micro-organisms can be supported.
Dr Wallis said: “Rosetta has already shown that the comet is not to be seen as a deep-frozen inactive body, but supports geological processes and could be more hospitable to micro-life than our Arctic and Antarctic regions”.
In the astronomers’ theory, the micro-organisms likely need liquid water bodies to colonise the comet and could live in cracks in its ice and ‘snow’. Organisms containing anti-freeze salts are particularly good at adapting to these conditions and some could be active at temperatures down to -40 degrees Celsius.
As P/67 Churyumov-Gerasimenko travels to its closest point to the Sun, a perihelion of 195 million km, the temperature is rising, gassing increasing and the micro-organisms would become more and more active.
Photo: ESA/Rosetta/NavCam – CC BY-SA IGO 3.0