VLT Survey Telescope
Alternative names | VST |
---|---|
Part of | Paranal Observatory |
Location(s) | Cerro Paranal, Antofagasta Province, Antofagasta Region, Chile |
Coordinates | 24°37′41″S 70°24′18″W / 24.628°S 70.40489°W |
Organization | European Southern Observatory |
Altitude | 2,635 m (8,645 ft) |
First light | 8 June 2011 |
Telescope style | Ritchey–Chrétien telescope |
Diameter | 2.65 m (8 ft 8 in) |
Secondary diameter | 0.938 m (3 ft 0.9 in) |
Angular resolution | 0.216 arcsecond |
Focal length | 14.416 m (47 ft 3.6 in) |
Mounting | altazimuth mount |
Website | vstportal |
Related media on Commons | |
The VLT Survey Telescope (VST) is a
The VST program is a cooperation between the
Technical information
The VST is an
Telescope optics
The telescope has two mirrors, the primary (M1) and a smaller secondary mirror (M2), which reflect light from the sky down to the OmegaCAM camera. Both mirrors are made from a crystalline ceramic material called
A computer-controlled
OmegaCAM
At its Cassegrain focus, the VST hosts an imaging wide-field camera (
VST surveys
The primary function of the VST is to support the Very Large Telescope by providing surveys – both extensive, multi-colour imaging surveys and more specific searches for rare astronomical objects. Three started in October 2011 as part of the Public Surveys Project,[12] and they are anticipated to take five years to carry out. These are the Kilo-Degree Survey (KiDS), VST ATLAS and the VST Photometric Hα Survey of the Southern Galactic Plane (VPHAS+). They focus on a wide range of astronomical issues from searching for highly energetic quasars to understanding the nature of dark energy.[13] More information about the surveys can be found on the ESO - The VST Surveys[14] website.
The data volume produced by OmegaCAM is large. About 30 terabytes of raw data will be produced per year and will flow back into data centres in Europe for processing. A novel and sophisticated software system has been developed at Groningen and Naples to handle the very large data flow. The end products from the processing will be huge lists of the objects found, as well as images, and these will be made available to astronomers worldwide for scientific analysis.[1] Funding for the data analysis was uncertain in 2011.[16]
Construction
The loss of the first mirror in 2002 while being transported from Europe to Chile caused delays in the construction of the telescope. The new primary and repaired secondary were completed in 2006.[4] Testing was finished in Italy and the telescope was dismounted, painted and packed, then shipped and mounted at Paranal. The first parts arrived in June 2007, and the first phase of integration at Paranal was completed in April, 2008.[8] The mirrors were stored while their cells were constructed; further delays occurred when the primary mirror cell suffered water damage while in transit to Chile, requiring it to be returned to Europe for repair.[6] The first images from the VST were released on June 8, 2011.[1]
Science
In planetary science, the survey telescope aims to discover and study remote Solar System bodies such as trans-Neptunian objects, as well as search for extrasolar planet transits. The Galactic plane will also be extensively studied with VST, which will look for signatures of tidal interactions in the Milky Way, and will provide astronomers with data crucial to understand the structure and evolution of our Galaxy. Further afield, the VST will explore nearby galaxies, extragalactic and intra-cluster planetary nebulae, and will perform surveys of faint object and micro-lensing events. The telescope will also peer into the distant Universe to help astronomers find answers to long-standing questions in cosmology. It will target medium-redshift supernovae to help pin down the cosmic distance scale and understand the expansion of the Universe. The VST will also look for cosmic structures at medium-high redshift, active galactic nuclei and quasars to further our understanding of galaxy formation and the Universe's early history.[17]
Through the VST ATLAS survey, the telescope will target one of the most fundamental questions in astrophysics today: the nature of dark energy. The survey aims to detect small-amplitude oscillations known as ´baryon wiggles’ that can be detected in the power-spectrum of galaxies and are the imprint of sound waves in the early Universe on the distribution of matter. The dark energy equation of state can be determined by measuring the features of these oscillations. Extrapolating from previous surveys, it is very likely that the VST will make some unexpected discoveries with major consequences for the current understanding of the Universe.[17]
First images
The first released VST image (below on the right) shows the star-forming region Messier 17, also known as the Omega Nebula or the Swan Nebula, as it has never been seen before. This vast region of gas, dust and hot young stars lies in the heart of the Milky Way in the constellation of Sagittarius (The Archer). The VST field of view is so large that the entire nebula, including its fainter outer parts, is captured — and retains its superb sharpness across the entire image. The data were processed using the Astro-WISE software system developed by E.A. Valentijn and collaborators at Groningen and elsewhere.[1]
The second released VST image (top on the right) may be the best portrait of the globular star cluster Omega Centauri ever made. Omega Centauri, in the constellation of Centaurus (The Centaur), is the largest globular cluster in the sky, but the very wide field of view of VST and its powerful camera OmegaCAM can encompass even the faint outer regions of this object. The view seen on the left includes about 300 000 stars. The data were processed using the VST-Tube system developed by A. Grado and collaborators at the INAF-Capodimonte Observatory.[1]
The third released VST image (middle on the right) shows a triplet of bright galaxies in the constellation of Leo (The Lion), together with a multitude of fainter objects: distant background galaxies and much closer Milky Way stars. The image hints at the power of the VST and OmegaCAM for surveying the extragalactic Universe and for mapping the low brightness objects of the galactic halo. The image on the left is a composite created by combining exposures taken through three different filters. Light that passed through a near-infrared filter was coloured red, red light is coloured green, and green light is coloured magenta.[19]
See also
- European Southern Observatory
- Large Synoptic Survey Telescope
- List of largest optical reflecting telescopes
- Very Large Telescope
- VISTA (telescope)
References
- ^ a b c d e f "First Images from the VLT Survey Telescope". ESO. 2011-07-28. Retrieved 2011-06-08.
- ^ a b "The VST Telescope". ESO. Retrieved 2011-07-29.
- Bibcode:2005Msngr.120...10C.
- ^ a b "The VST mirror". ESO. Retrieved 2011-08-01.
- ^ Bibcode:2003MSAIS...3..286C.
- ^ ISBN 978-0-521-89993-2.
- ^ The Jewel on the Mountaintop, Claes Madsen, European Southern Observatory 2012, https://www.eso.org/public/archives/books/pdf/book_0050.pdf
- ^ a b "VSTceN Portal: VLT Survey Telescope Center at Naples Web Portal". INAF. Archived from the original on 2007-03-05. Retrieved 2011-08-01.
- Bibcode:2005Msngr.120...13C.
- ^ Kuijken, Konrad, Ralf Bender, Enrico Cappellaro, Bernard Muschielok, Andrea Baruffolo, Enrico Cascone, H-J. Hess; et al. (2004). OmegaCAM: Wide-field imaging with fine spatial resolution (PDF). Ground-based Instrumentation for Astronomy. Vol. 5492. International Society for Optics and Photonics. pp. 484–494.
{{cite conference}}
: CS1 maint: multiple names: authors list (link) - ^ "Huge New Survey to Shine Light on Dark Matter". Retrieved 13 July 2015.
- ^ "ESO - Public Surveys Projects".
- ^ "The VST surveys". ESO. Retrieved 2011-08-01.
- ^ "The VST surveys".
- ^ "A Tale of Three Stellar Cities". www.eso.org. Retrieved 27 July 2017.
- ^ "AAAS".
- ^ a b "VST Science". ESO. Archived from the original on 2011-08-14. Retrieved 2011-08-01.
- ^ "Image of the Carina Nebula Marks Inauguration of VLT Survey Telescope". ESO Press Release. Retrieved 8 December 2012.
- ^ "News". ESO. 2011-07-27. Retrieved 2011-08-01.