The ALMA project, that will revolutionise our knowledge of the Universe, now has a sufficient number of antennas in place to produce its first science observations. The 16th antenna, also the first European antenna to reach the observatory's Array Operations Site, joined antennas from the other international ALMA partners on 27 July 2011. Each 12-metre diameter antenna is located at the Chajnantor plateau, 5,000 metres above sea level in the Atacama Desert in Chile. The addition of the 16th antenna means that astronomers will shortly begin using ALMA to conduct new scientific research.

ALMA (Atacama Large Millimetre/sub-millimetre Array) is a huge high frequency radio telescope that will eventually be made up of 66 individual antennas. When electronically combined they will simulate a telescope diameter of up to 16km - more than a thousand times the diameter of a single individual antenna within the array. Its vast size will allow astronomers to detect signals within and outside of our galaxy with greater clarity than has previously been possible.

The first European antenna, manufactured by the European AEM Consortium [1] under contract from the European Southern Observatory (ESO), was handed over to ESO in April after six months of testing. Assembled at the Operational Support Facility at an altitude of 2,900 metres in the foothills of the Chilean Andes, it was equipped with highly sensitive detectors, which are cooled, and other necessary support electronics. Now, one of the giant ALMA transporter vehicles has taken it 28km further up the plateau and along the dry desert road to the Array Operations Site (AOS) location at 5,000m altitude. The AOS is the last port of call in a long journey that began when the component parts of the antenna were manufactured in factories across Europe, under the rigorous oversight of ESO.

The ALMA Antenna Project Manager at ESO, Stefano Stanghellini said, "It is great to see the first European ALMA antenna reach Chajnantor. It's from this arid plateau that these masterpieces of technology will be used to study the cosmos."

The UK's involvement in ALMA includes STFC's Rutherford Appleton Laboratory and UK Astronomy Technology Centre, the Cavendish Laboratory at the University of Cambridge, the University of Manchester and the University of Kent, all of whom played key roles in the design and construction of ALMA. The Science and Technology Facilities Council allows UK astronomers access to ESO's telescopes through a process of national subscription.

John Richer, UK Project Scientist for ALMA, based at the University of Cambridge said; "Even with only 16 of the total 66 antennas in place, ALMA is a huge step forward for astronomy. The observatory is already much more sensitive than current instruments, and will allow us to study in great detail the faint radio waves emanating from young stars and distant galaxies.  We hope these observations will answer some of the most fundamental questions about the way the Universe evolved from the Big Bang to the present day, and how our own Sun and planetary system formed". 

ALMA's early science observations are planned to begin later this year. Although ALMA will still be under construction, the 16-antenna array that will be available will already be far more sensitive than all other telescopes of this kind. Astronomers from around the world have submitted almost 1000 proposals for early science observations. This level of demand is about nine times the number of observations that are expected to be carried out during the first phase of early science, which demonstrates how excited researchers are to use ALMA, even at this stage of the project.

More detailed information can be found in ESO's press ​release (link opens in a new window) marking the arrival of the 16th and first European antenna on the high site.

Notes to editors

1] The AEM Consortium is composed of Thales Alenia Space, European Industrial Engineering, and MT-Mechatronics.

ALMA, an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

Twenty-five European ALMA antennas, including this one, are being provided by ESO through a contract with the European AEM Consortium. ALMA will also have 25 antennas provided by North America, and 16 by East Asia.

Images

Images of the 16th and first European antenna to reach the high site are available in ESO's press release (link opens in a new window).