Like millions over people I was cheered to see that the probe Philae landed successfully on the 67P/Churyumov-Gerasimenko comet after a 6.4 billion km ten year journey. In a mission this complex there will inevitably be a few hiccups and the biggest one so far has been that the probe has been unable to secure itself to the surface. The gravity of a comet is less than 0.1 % of that of the Earth, meaning effectively that the probe weighs only a few ounces.
One thing that struck me is that how with our currently technology long voyages such as this can only be undertaken by unmanned spacecraft. It would just not be possible to put astronauts on spacecraft for ten years. The human body would not be able to cope with 10 years of weightlessness, plus the astronauts would almost certainly develop cancer from the harmful radiation in space which would penetrate through the walls of the spacecraft.
Mrs Geek and I enjoyed watching on TV last night the elation and excitement of Professor Monica Grady, a British Professor of Planetary Science, who had been working on this project for 25 years and was overwhelmed with emotion at the successful outcome. We found out today that she is in fact the sister of one of Mrs Geek’s friends, so we are proud to be associated with such an illustrious family!
Explaining Science 