Cosmic rays from space used to uncover secret of Victorian Railway Tunnel
Cosmic ray technology used to find hidden chambers in the Great Pyramid at Giza is helping National Highways to unlock the secrets of a historic railway tunnel located deep under the streets of Glasgow. Balgray Tunnel, constructed in 1896, curves for 640 metres under the busy Kelvinside area of Glasgow and although it has been closed since 1964 it still needs regular inspections to ensure it remains safe and in good order.Until now techniques such as ground penetrating radar, drilling and visual inspections have been used to check for hidden shafts and highlight potential issues.

Now a novel process called muon imaging, which harnesses cosmic rays from space to create powerful x-ray like images, is being used to search for potential defects and voids without having to be in physical contact with the tunnel walls and ceiling - so avoiding the need for access at height.