Astronomers slice up galaxies
The instrument, an Imaging Spectrometer known as UIST, has the revolutionary capability to 'slice' an image into sections. This image slicing technique allows astronomers to create three-dimensional views of the conditions throughout entire galaxies in a single observation., ,At the heart of UIST is an extremely sensitive electronic detector with over a million pixels. On its very first night of operation UIST was able to penetrate across the 47 million light years that separate spiral galaxy NGC1068 from Earth to reveal the detailed structure in the centre of the galaxy. NGC1068 is known to have an active nucleus, or centre, which has produced intriguing structures, making it an ideal target for the image slicer. By slicing the light from an astronomical object into sections and studying the resulting spectra - rather like the rainbow produced when light passes through a glass prism - astronomers can detect the chemical composition of stellar gases and investigate the interactions between stars and cosmic dust in complex objects like galaxies. The slicer creates a 'data cube' of the galaxy's nucleus which can be sliced in one direction to show the nucleus at a single infrared wavelength, or at right angles to produce spectra across the entire nucleus. , ,During its first night on the telescope UIST was also trained on the Omega Nebula. This nebula is a gas cloud where new stars are forming. Located 5000 light years from Earth, the Omega Nebula is nevertheless a near neighbour and can be studied in exquisite detail with an instrument such as UIST. The intense ultraviolet radiation from young, hot stars blasts the atoms in clouds of interstellar gas, making them glow brightly as seen in the bottom right of the UIST image. This beautiful picture shows the Omega Nebula in more detail, and is a sharper image, than any previous picture., ,Dr Andy Adamson, Science Director of UKIRT, is extremely excited about the future with UIST. "Combining the power of UISTs imaging and spectroscopy with the telescope's excellent image quality will revolutionise observations at UKIRT. We'll be able to image objects of interest and analyse them spectrally, all with the same instrument. UIST will give astronomers using UKIRT a unique way of viewing the Universe, and will maintain the telescope's position at the leading edge of science.", ,UIST was designed and built at the UK Astronomy Technology Centre (UK ATC) in Edinburgh and presented some major technological challenges as lead scientist Dr Suzanne Ramsay Howat explained, "At infrared wavelengths the ambient heat of the instrument itself causes unwanted background light that would distort our findings. To avoid this the entire instrument, weighing 750kg, is cooled inside a cryostat to about -200 degrees C, just 70 degrees above absolute zero." , ,At these temperatures components within the instrument shrink placing increased technical demands on the design team. In particular wheels the size of dinner plates, that allow different optical components to be selected, have to be rotated to within 1/250 of a degree whilst precisely maintaining the alignment of the optical pathways - no mean feat in such extremes of cold. "We are delighted to see our solutions working so well on the telescope." Dr Ramsay Howat added., ,Dr Adrian Russell, the Director of the UK ATC commented "The delivery of this state of the art instrument clearly demonstrates the capabilities of the UK ATC to bring its technological innovation to extremely demanding scientific projects. The UIST team are justifiably proud of their success. After five years of work in the laboratories here in Edinburgh it is exciting to be able to achieve this level of image quality with a British instrument on a British telescope." ,NOTES TO EDITOR Images, ,1. The active galaxy NGC1068, imaged using the Integral Field Unit, or 'image slicer'. The greyscale image in the foreground shows the galactic nucleus in combined infrared light. Above is an image slice at a single wavelength, and to the right is a spectral slice showing the spectra across the entire nucleus., ,2. UIST infrared image of the Omega Nebula, a site of star formation 5000 light years from Earth., ,3. The UK Infrared Telescope (UKIRT), on Mauna Kea, Hawaii - UIST's new home., ,Images are courtesy of the Royal Observatory, Edinburgh and can be dowloaded from www.pparc.ac.uk ,UIST, ,The UKIRT Imaging Spectrometer (UIST) was designed and built at the UK Astronomy Technology Centre (UK ATC) in Edinburgh. It detects infrared light with wavelengths between 1 and 5 microns with a 1024 x 1024 pixel Indium Antimonide detector array. It can be used for imaging, spectroscopy, integral field spectroscopy, and polarimetry. These multiple abilities allow it to replace almost all the existing instrumentation on UKIRT. It cost just under UKP 3M to build and was funded by the Particle Physics and Astronomy Research Council (PPARC). It will enable astronomers to take advantage of the better image quality that resulted from the UKIRT Image Upgrades Programme that was completed in 1998., ,First Light Targets, ,NGC1068 is a Seyfert 2 galaxy located at 47million light years from Earth. It has an active galactic nucleus surrounded by a ring, or torus, of molecular gas. , ,The Omega Nebula (Messier 17) is a gas cloud that is a site of vigorous star formation. It is located in our own galaxy at a distance of 5000 light years from Earth. The intense ultraviolet radiation from young, hot stars blasts the atoms in clouds of interstellar gas. The clouds glow brightly, as seen in blue in the bottom right of the UIST image. At some distance from the new stars, the starlight stops destroying the cloud. This is marked by the sharp transition from light to dark running diagonally across the picture. Behind this line, astronomers can study the original gas cloud, seeking to understand the process of stellar birth., ,The UK ATC, ,The UK Astronomy Technology Centre is located at the Royal Observatory, Edinburgh (ROE). It is a scientific site belonging to the Particle Physics and Astronomy Research Council (PPARC). The mission of the UK ATC is to support the mission and strategic aims of PPARC and to help keep the UK at the forefront of world astronomy by providing a UK focus for the design, production and promotion of state of the art astronomical technology., ,The ROE, ,The Royal Observatory, Edinburgh comprises the UK Astronomy Technology Centre (UK ATC) of the Particle Physics and Astronomy Research Council (PPARC), the Institute for Astronomy (IfA) of the University of Edinburgh and the ROE Visitor Centre., ,UKIRT, ,The UK Infrared Telescope is operated by the Joint Astronomy Centre in Hilo, Hawaii, on behalf of the UK Particle Physics and Astronomy Research Council. It has a 3.8m mirror, and is the worlds largest telescope dedicated solely to infrared astronomy., Contacts, ,Eleanor Geer 0131 668 8397,PR Officer, ROE efg@roe.ac.uk, ,Peter Barratt 01793 442025,Head of Communications, PPARC peter.barratt@pparc.ac.uk, ,Douglas Pierce-Price +1 808 969 6524,Science Outreach specialist, UKIRT pierce-price@jach.hawaii.edu, Websites, ,http://www.roe.ac.uk/atc/projects/uist/index.html,http://www.jach.hawaii.edu/JACpublic/UKIRT/instruments/uist/uist.html,http://www.pparc.ac.uk/,http://outreach.jach.hawaii.edu/articles/aboutukirt/ PPARC,The Particle Physics and Astronomy Research Council (PPARC) is the UKs strategic science investment agency. It funds research, education and public understanding in four broad areas of science - particle physics, astronomy, cosmology and space science. PPARC is government funded and provides research grants and studentships to scientists in British universities, gives researchers acess to world-class facilities and funds the UK membership of international bodies such as the European Organisation for Nuclear Research, CERN, the European Southern Observatory and the European Space Agency. It also contributes money for the UK telescopes overseas on La Palma, Hawaii, Australia and in Chile, the UK Astronomy Technology Centre at the Royal Observatory, Edinburgh and the MERLIN/VLBI National Facility.
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