The new device will investigate the origins of the Milky Way

The new device will investigate the origins of the Milky Way


Where do the stars come from in our night sky?

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 detect 1,000 stars per hour until it has cataloged a total of five million.

A super-fast mapping device connected to WHT will analyze the composition of each star and the speed at which it travels.

It will show how our galaxy, the Milky Way, was built over billions of years.

Professor Gavin Dalton of the University of Oxford has devoted more than a decade to developing the instrument, known as the “Weave”.

He told me he was “over excited” that he is ready to go.

“It’s a fantastic accomplishment from a lot of people that this happens and it’s great that it works,” he said. “The next step is the new adventure, it’s brilliant!”

Intertwining instrument: it looks like a large metal disc crossed by fiber optic tubes that point to all points of the compass.  Robotic arms hover over it.

Weave’s nimble robotic fingers precisely place a thousand optical fibers, each pointing at a star

Weave was installed on the WHT, which sits atop a mountain on the Spanish island of La Palma, Canary. The name stands for WHT Enhanced Area Velocity Explorer – and that’s exactly what it does.

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

For each piece of sky the WHT is pointed at, astronomers identify the positions of a thousand stars. Weave’s nimble robotic fingers then carefully place an optical fiber – a tube that transmits light – at exactly each location on a plate, pointing at the corresponding star.

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

All of this is completed in just one hour. As this happens, the optical fibers for the next thousand stars are placed on the opposite side of the plate, which flips over to analyze the next set of targets once the previous investigation is complete.

Milky Way

Graphics: The Milky Way is surrounded by “dwarf” satellite galaxies.

Our galaxy is a dense spiral vortex with up to 400 billion stars. But it started out as a relatively small collection of stars.

It has grown from successive mergers with other small galaxies over billions of years. In addition to adding stars from new galaxies joining ours, each merger elicits enough things to lead to a brand new star formation.

Weave is able to calculate the speed, direction, age and composition of each star it observes, essentially creating a moving image of stars moving in the Milky Way. According to Prof Dalton, extrapolating backwards, it will be possible to reconstruct the entire formation of the Milky Way in details never seen before.

“We will be able to trace the galaxies that were absorbed as the Milky Way formed in cosmic time – and see how each absorption triggers the new star formation,” he said.

Dr Marc Balcells, who is the general manager of the WHT, told BBC News he believed Weave would lead to a major shift in our understanding of how galaxies are made.

” We have felt for decades that we are in a golden age of astronomy, but what the future awaits is far more important.

“Weave will answer the questions that astronomers have been trying to answer for decades, such as how many pieces come together to form a large galaxy and how many galaxies have been joined to form the Milky Way?”

Control room

Instrumentation specialist Dr. Cecilia Farina says Weave could discover completely unexpected phenomena

Dr Cecilia Farina, the project’s instrumentation specialist, said she believed Weave would make astronomy history.

“There are a huge amount of things we’re going to find that we weren’t expecting to find,” he said. “Because the Universe is full of surprises.”

You can see Weave and other new telescopes in action in a short film, The Cosmic Hunters, on BBC iPlayer.

Follow Pallab on Twitter

Leave a Reply

Your email address will not be published.