Scientists use William Herschel Telescope to reveal unprecedented details of our galaxy

Scientists have supercharged one of Earth’s most powerful telescopes with new technology that will reveal how our galaxy formed in unprecedented detail. The William Herschel Telescope (WHT) in La Palma, Spain will be able to survey 1,000 stars per hour until it has catalogued a total of five million.


William Herschel Telescope


A super-fast mapping device linked up to the William Herschel Telescope will analyze the make-up of each star and the speed at which it travels. It will show how our Milky Way galaxy was built up over billions of years.


Prof Gavin Dalton of Oxford University has spent more than a decade developing the instrument, known as ‘Weave’. “It’s a fantastic achievement from a lot of people to make this happen and it’s great to have it working,” he said. “The next step is the new adventure, it’s brilliant!”


Weave instrument: It looks like a large metal disk criss-crossed by fibre-optic tubes pointing at all points of the compass. Robotic arms hover over it.


Weave has been installed on the William Herschel Telescope, which sits high on a mountain top on the Spanish Canary Island of La Palma. The name stands for William Herschel Telescope Enhanced Area Velocity Explorer – and that’s exactly what it does.


It has 80,000 separate parts and is a miracle of engineering.


Identifying Position of thousand stars


For each patch of sky the William Herschel Telescope is pointed at, astronomers identify the positions of a thousand stars. Weave’s nimble robotic fingers then carefully place a fibre-optic – a light-transmitting tube – precisely on each location on a plate, pointing towards its corresponding star.


These fibres are in effect tiny telescopes. Each one captures light from a single star and channels it to another instrument. This then splits it into a rainbow spectrum, which contains the secrets of the star’s origin and history.


All this is completed in just one hour. While this is going on, fibre optics for the next thousand stars are positioned on the reverse side of the plate, which flips over to analyse the next set of targets once the previous survey has been completed.