Mister blue sky

’s collaboration with online travel agent

to find the world’s bluest sky has brought unforeseen benefits for the future of affordable, transportable spectrometry.

Expedia sent its ‘Blue Sky Explorer’, Anya, on a 103,000km trip with a portable spectrometer, specially built for the project by NPL, to measure the colour of the sky around the world. Rio de Janeiro in Brazil topped the chart, followed by Bay of Islands in New Zealand and Ayers Rock in Australia. Of the candidates in the British Isles, Castell Dinas Bran in Wales came 9th, Dublin 12th, Edinburgh 18th and Cornwall 20th.

Dr Nigel Fox, Head of Science at NPL’s Optical Radiation Measurement group, said, ‘We built the spectrometer for this experiment from scratch using cheap, lightweight alternatives to our lab-based equipment. It also had to be robust enough to survive the trip. For the first time, we documented clear procedures, so anyone can do good measurement using this equipment.