Monday February 2^nd 2009. Launch -73 days.

We have received one huge piece of good news today. We have now passed a critical landmark that you will probably never find in the Press but, without it, there is no launch: today the Ariane 5 rocket that will launch Herschel arrived, by boat, at Kourou. Actually, it is not quite true that the rocket arrived at Kourou: really, it was the world’s large construction kit arrived at Kourou. Now, the engineers will take the different bits and mount them (they would say “integrate them”) to give the launcher that will be rolled out onto the launch pad in April.

Initially, Ariane was almost exclusively a French venture, but has been made far more international in recent years, although the French influence in the launch team is huge and Kourou is French territory. The launch team has built up a formidable reputation over the years, with few failures. The Ariane 5 on a quite extraordinary run of success in a field where the failure of a single component of millions can lead to a catastrophic failure (there is no gliding the rocket into a soft landing in the Hudson River if you lose your engines). Still, even if the probability of launch success were 98%, which would be a fantastic success rate, the 2% probability of failure adds up, launch after launch: the probability of 10 consecutive successes would be a quite decent 82%; the probability of 20 consecutive successes though drops to 67% (i.e. there would be one chance in 3 that you could not string together 20 successes). How many launches does it take before the probability of having no failures in the sequence drops below 50%? The answer is, only 35. That is why, for a rocket to be man-rated, the probability of success per launch has to be so high. Of course, we all know that even if the last launch was a success, the probability of failure of the next remains 2%, or whatever the exact figure is for the Ariane 5, but we still get nervous!

In other senses, today has been less satisfactory. Day 1 of the Simulations has not gone as smoothly as I would have liked and that opinion had to be expressed fairly forcefully. Tomorrow morning we will see if the routines that distribute the data from the spacecraft to the instrument teams have worked well. If they have, I will feel happier. We have a good team and a good team spirit and it is early days yet. We knew that the first week might be tricky and right now we are not as well prepared as I would have liked.

Today I had a second master class in our system. Going in with a fresher and less tired mind helped: it is fearsomely complicated and very intimidating at first sight, but being systematic and extremely careful is the key. The job consists of being the nexus for all the observations that come from the instrument teams, ensuring that there are no errors, seeing that nothing gets through that might damage the satellite and that nothing is missing that would stop the observations being scheduled.

Last night my later evening relaxation was to watch the film “Don Camilo” on the DVD. Wonderful! Mind you, I’m not sure what today’s Press would make of a village priest like that these days. It took my mind off the weather. After yesterday’s snow today it just rained and rained and rained. Mind you, the jacket kept me absolutely dry, as did my impermeable over-trousers, although I arrived with my shoes and socks absolutely soaked through. Yuk!!! Yes, I did get cold feet this morning…