The oversight board for Alma has authorised the design and building of an additional set of receivers, which will enable the telescope to access a part of the spectrum of light that it cannot currently study. The receivers will be built by an international consortium in which Chalmers and Onsala Space Observatory play key roles.
Hans Olofsson, professor of radio astronomy at Chalmers and director of Onsala Space Observatory, is delighted by the new task.
“We´re very pleased to be involved in making Alma one of the biggest and best observatories of our time. The contract is worth 50 million SEK for Chalmers over 5 years. During the period Alma is under construction a total of 180 million SEK will be returned to Sweden in the form of contracts”, he says.
Alma – the Atacama Large Millimeter/submillimeter Array – is the world’s largest astronomy project. This powerful new facility on the Chajnantor plateau in Chile is giving astronomers insight both into how the Universe and its galaxies have evolved since the Big Bang, and how stars and planetary systems formed in our own galaxy. Although only half of its final total of 66 antennas are currently in place at high altitude in northern Chile, Alma is already operating and making scientific observations with a partial array.
“Alma´s first discoveries have already given us a taste of what awaits us when the telescope is completed in 2013. But we won´t stop there. These new receivers will make it possible for us to take even better advantage of Alma´s fantastic site on Chajnantor”, says Wolfgang Wild, European project manager for Alma.
The new receivers were originally designed, developed, and prototyped by Onsala Space Observatory´s Advanced Receiver Development group, based at Chalmers. Six of these receivers have already been built and supplied to Alma (see previous press release
, December 2010).
One of the first six “Band 5” receiver cartridges built for Alma. Extremely weak signals from space are collected by the Alma antennas and focused onto the receivers, which transform the faint radiation into an electrical signal.
Photo: Onsala Space Observatory/Alexey Pavolotsky
Over the next five years, all 66 of Alma´s antennas will be equipped with these new receivers. To do this, including spares, another 67 units need to be built.
“Our role will be to, together with our colleagues in the Netherlands, manufacture 67 new receivers that are just as sensitive as the six that we have already built in our lab in Gothenburg”, says Victor Belitsky, professor of radio and space science at Chalmers, who will be technical lead for the consortium.
The receivers will be used to study some of the earliest galaxies in the Universe and will help us to understand when some of the first stars formed. They will also enhance astronomers´ abilities to measure the presence of water – a molecule essential to life – in the dusty disks where planets are believed to form, and in the atmospheres of planets and comets in our own Solar System.
Water in space can be tricky to measure accurately, because of the confusing effects of observing through the water vapour in Earth´s atmosphere. The way in which Alma´s “Band 5” receivers will measure water reduces some of these difficulties.
The decision to fund this enhancement of Alma, even before the telescope is completed, was made by the Alma Board in April 2012. On 9 May 2012, the decision was approved by ESO´s Finance Committee. The upgrade is expected to be completed in 2016.
More about the receivers
Chalmers scientists are producing the new receivers in collaboration with the Rutherford Appleton Laboratory, UK, and the European Southern Observatory (ESO)
, under the European Commission (EC) supported Framework Programme FP6 (Alma Enhancement)
, starting in 2006. Six of these receivers have been built under the FP6 contract and supplied to Alma.
The 67 new units will be built by Europe with contributions from the United States. ESO will place the European contract for the cryogenically cooled receivers, and oversee their development. The consortium leader will be Nova
, the research school for astronomy in the Netherlands. The receivers will be fabricated by Nova in partnership with Onsala Space Observatory´s Advanced Receiver Development group. In North America, the National Radio Astronomy Observatory (NRAO)
will build the high-precision oscillators that will tune the receivers, so that the output from all antennas can be precisely combined to make high-resolution images.
More about Alma (Atacama Large Millimeter/submillimeter Array)
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.
Alma observes the Universe in radio waves: light which is invisible to our eyes. Extremely weak signals from space are collected by the Alma antennas and focused onto the receivers, which transform the faint radiation into an electrical signal. The new “Band 5” receivers will be able to detect electromagnetic radiation with wavelengths between about 1.4 and 1.8 millimeters (211 and 163 gigahertz), one of the ranges of the spectrum to which Earth´s atmosphere is partially transparent, which allows the light to reach the Alma antennas.
More about Onsala Space Observatory
Onsala Space Observatory is Sweden´s national facility for radio astronomy. The observatory provides researchers with equipment for the study of the Earth and the rest of the universe. It operates two radio telescopes in Onsala, 45 km south of Gothenburg, and participates in several international projects. The Department of Space and Earth Science at Chalmers University of Technology hosts the observatory, which is operated on behalf of the Swedish Research Council.
For more information and images please contact:
Robert Cumming, astronomer and communications officer, Onsala Space Observatory, +46 31 772 55 00 or +46 704 93 31 14, firstname.lastname@example.org
Victor Belitsky, Professor of Radio and Space Science at Chalmers University of Technology, leader of the Group for Advanced Receiver Development, +46 31 772 18 93, email@example.com
The giant telescope Alma is now more than halfway to completion, with 39 of 66 antennas in place on the Chajnantor plateau in the Atacama desert in northern Chile. Alma is the world’s most complex ground-based telescope, expected to be completed in 2013. Pictures: the European Southern Observatory (ESO)