Rosetta mission's historic scientific feat

The European Space Agency’s Rosetta mission which landed robotic spacecraft Philae on comet 67P/Churyuomov-Gerasimenko last week is a historic scientific achievement.

The information gained from the expedition will add enormously to our understanding of the solar system, though it was not 100 per cent successful.

The feat of taking the spacecraft to the comet and landing it on the comet was forbiddingly difficult and complex. It involved travelling a distance of 6.5 billion km from the earth and landing the spacecraft on the comet racing towards the sun at 1,35,000 km per hour. 

Rosetta was launched 10 years ago for this rendezvous and the advance planning and calculations had to be correct to the millisecond to reach the comet – which is over 4 km long and wide – get into an orbit around it and drop Philae with its package of sensory instruments on it. It is the farthest expedition that made physical contact with a heavenly body and reported back to earth.

Philae was expected to make a smooth landing and send pictures and information about the composition of the comet and its environment. But the touchdown was less than perfect and the spot was some distance away from the chosen area.

It bounced back from the surface but landed again and is now resting at a place where there is not enough sunlight to recharge its batteries.

But it has done most of the work it was expected to do in its brief active life of 60 hours on the comet and the results of the investigations are very valuable. The failure to make a good landing itself provided useful information that the surface of the comet, made of rock, ice and dust, is harder than expected.

More important is the detection of organic molecules in the comet’s atmosphere. This is important because there is a strong view that life on earth, whose building blocks are organic compounds and water, originated from contact with a comet.

The level of complexity of the compounds found on 67P might help scientists to test the theory.

Comets are ancient wanderers from the depths of the solar system who have stories to tell as they were participants and witnesses to events that happened over billions of years.

They are remnants of the formation of the solar system and their study will shed light on its beginning and evolution.

There are even views that they could be harnessed for use on earth. Rosetta will continue to orbit 67P for 17 months and collect more data and send them to earth. The mission has made a great beginning in the study of comets.