PARIS: Astronomers have come up with a novel explanation for a strange appearance of the comet carrying Europe’s robot probe Philae through outer space: alien microscopic life.

Many of the frozen dustball features, which include a black crust over lakes of ice, flat-bottomed craters and mega-boulders scattered on the surface, were “consistent” with the presence of microbes, they said.

Observations by the European Space Agency’s Rosetta comet orbiter have shown that 67P/Churyumov-Gerasimenko “is not to be seen as a deep-frozen inactive body, but supports geological processes”, Max Wallis of the University of Cardiff said in a statement issued by Britain’s Royal Astronomical Society (RAS).

In fact, the comet racing towards the Sun at a speed of 32.9 kilometres per second, “could be more hospitable to micro-life than our Arctic and Antarctic regions”. Wallis and his colleague Chandra Wickramasinghe of the Buckingham Centre for Astrobiology, presented their theory to a meeting of the RAS in Llandudno, Wales, on Monday.

They pointed to Rosetta’s detection of complex organic material, which gave the comet its surprisingly super-dark and low-reflecting surface, as “evidence for life”. Furthermore, Wickramasinghe said, 67P’s gas ejections started “at distances from the Sun too far away to trigger surface sublimation”.

This implied that micro-organisms under the comet’s surface had been “building pockets of high pressure gases that crack overlying ice and vent organic particles”, he said by email. Micro-organisms could use liquid water to colonise the comet-- infiltrating cracks in the ice and “snow” during warmer periods when the cosmic wanderer is nearer the Sun, the duo said.

Published in Dawn, July 7th, 2015

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