“I have postulated a particle that cannot be detected.” Those were the words uttered by the eminent physicist Wolfgang Pauli in 1930 when he first put forward the idea of the neutrino. Such is the delightful eccentricity of physicists of Pauli’s ilk, he wagered a crate of champagne on the discovery. It would be 12 years before anyone would propose an idea to actually detect a neutrino, and another 14 years before it would be confirmed that neutrinos had actually been seen.
In fact, Pauli was nearly right. Neutrinos have no charge, virtually no mass, and they can travel across cosmic distances without interracting with any matter at all. Don’t let that fool you, however – neutrinos are everywhere. This image was taken using neutrinos instead of light. It’s actually a picture of the Sun, imaged entirely with neutrinos by the Japanese Super-Kamiokande (or Super-K) experiment built in an abandoned mine.
The image has added coolness value because it was also taken at night! Where do you look for the Sun at midnight? The answer is that you look straight down. The neutrinos used to take this 500 day exposure all passed straight through our entire planet! Centred on the Sun, creating that bright spot in the centre, the whole image actually covers a quarter of the entire sky – 90° x 90°.