Alma telescope begins study of cosmic dawn

[Gerald]

One of the 21st Century's grand scientific undertakings has begun its quest to view the "Cosmic Dawn".

The Atacama large milllimetre/submillimetre array (Alma) in Chile is the largest, most complex telescope ever built.

Alma's purpose is to study processes occurring a few hundred million years after the formation of the Universe when the first stars began to shine.

Its work should help explain why the cosmos looks the way it does today.

One of Alma's scientific operations astronomers, Dr Diego Garcia, said that the effective switching on of the giant telescope ushered in a "new golden age of astronomy".

Pallab Ghosh looks around the array of giant antennas that makes up the telescope, on one of the highest plateaus in Chile

"We are going to be able to see the beginning of the Universe, how the first galaxies were formed. We are going to learn so much more about how the Universe works," he told BBC News.

Alma consists of an array of linked giant antennas on top of the highest plateau in the Atacama desert, close to Chile's border with Bolivia.

It has been under construction since 2003. With the addition of new antennas, the telescope has been able to see progressively deeper into the cosmos and discern star formation processes in ever greater detail.

The full testing and commissioning of its 20th antenna has enabled Alma to record events that have never been seen before. It is now that the first scientific discoveries can be made.



As a taster of what is to come, the European Southern Observatory, one of the organisations that run the facility, has released the first images taken by Alma. They show - perhaps appropriately for the occasion - the collision of two galaxies known as the Antennae Galaxies.

These colossal collections of stars can be seen using optical telescopes, such as the Hubble Space Telescope. But Alma, which gathers light that is not visible to the eye, is able to pick out clouds of dense cold gas from which new stars form.

The images show concentrations of the star-forming gas at the centres of each galaxy and also in the chaotic region where they are colliding. It is here that new stars and planets will be born.

The image was taken using just 12 antennas. The sharpness and resolution of images will increase dramatically as more antennas are added. The aim is for Alma to have 66 antennas by 2013.

http://www.bbc.co.uk/news/science-environment-15107254




Note: 3 October 2011 Last updated at 09:30 GMT