All the fun of the Astrofair

On Saturday I spent an extremely entertaining day in Sidmouth, not on one of the town's beaches, but instead at an astronomical observatory.

I confess that, while I knew about Norman Lockyer, I wasn't aware of the Norman Lockyer Observatory - and it's a wonderful find.

Lockyer was a professor at Imperial College (or, rather, its predecessor) and one of his main studies was the Sun. Using spectroscopy - splitting the light from the Sun into a colour spectrum, where dark lines indicate the presence of atoms that are absorbing particular energies of photons - Lockyer discovered a puzzling line in the yellow band, which had not been seen before. He had discovered an element that had not yet been found on the Earth, and named it after the Greek word for the Sun, helios. As well as discovering helium, Lockyer brought another significant presence of modern science into being when he founded a journal called Nature, one of the most prestigious scientific journals today.

When he retired to Devon, Lockyer established an observatory, which has grown to be today's Norman Lockyer observatory. Apart from a handful of telescope domes, the facilities now include an excellent lecture theatre and planetarium, and, for the fair on Saturday, an array of marquees that took me back to my youthful delight in all things astronomical. If the cash had been available I could have spent thousands on the technology on sale - and even without cash I was pressed into taking part in an experiment when I dared to enter the Institute of Physics tent.

I was there primarily to give a talk, based on Before the Big Bang, which seemed to go down well - but also took part in the fair and spent a lot of time next to a fascinating stand where a collection of stellar spectra on glass plates, mostly over 100 years old, was on display and could even be picked up and looked at. The archive, under the aegis of Exeter University and the Observatory, has apparently over 7000 of these plates which need cataloguing (the old catalogue was lost) and scanning in high res to preserve their delicate and valuable contents - after all these are records of spectra made before the light pollution we so decry to today.

All in all a brilliant day, and if you are anywhere near the West Country, I urge you to turn up at next year's fair - or at one of the observatory's many other events through the year. You can discover their programme and much about it at their rather quirky (bear with it) website.

I just wish I had taken some photos - but I was having too much fun!