Gran Telescopio Canarias

Gran Telescopio Canarias

Gran Telescopio Canarias, 2008
Alternative names	GranTeCan
Location(s)	La Palma, Atlantic Ocean, international waters
Coordinates	28°45′24″N 17°53′31″W / 28.75661°N 17.89203°W / 28.75661; -17.89203
Altitude	2,267 m (7,438 ft)
Diameter	10.4 m (34 ft 1 in)
Collecting area	78.54 m2 (845.4 sq ft)
Focal length	169.9 m (557 ft 5 in)
Website	www.gtc.iac.es
Location of Gran Telescopio Canarias
Related media on Commons
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The Gran Telescopio Canarias (GranTeCan or GTC) is a 10.4 m (410 in) reflecting telescope located at the Roque de los Muchachos Observatory on the island of La Palma, in the Canary Islands, Spain. It is the world's largest single-aperture optical telescope.^[1]

Construction of the telescope took seven years and cost €130 million.^[2][3] Its installation was hampered by weather conditions and the logistical difficulties of transporting equipment to such a remote location.^[4] First light was achieved in 2007 and scientific observations began in 2009.^{[citation needed]}

The GTC Project is a partnership formed by several institutions from Spain and Mexico, the University of Florida, the National Autonomous University of Mexico,^[5] and the Instituto de Astrofísica de Canarias (IAC). Planning for the construction of the telescope, which started in 1987, involved more than 1,000 people from 100 companies.^[3] The division of telescope time reflects the structure of its financing: 90% Spain, 5% Mexico and 5% the University of Florida.

The GTC began its preliminary observations on 13 July 2007, using 12 segments of its primary mirror, made of Zerodur glass-ceramic by the German company Schott AG. Later, the number of segments was increased to a total of 36 hexagonal segments fully controlled by an active optics control system, working together as a reflective unit.^[4][6] Its first instrument was the Optical System for Imaging and low Resolution Integrated Spectroscopy (OSIRIS). Scientific observations began in May 2009.^[7]

The Gran Telescopio Canarias formally opened its shutters on July 24, 2009, inaugurated by King Juan Carlos I of Spain.^[8] More than 500 astronomers, government officials and journalists from Europe and the Americas attended the ceremony.

GTC hosts a suite of advanced instruments, including:

• OSIRIS: Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy The IAC's OSIRIS (Optical System for Imaging and low Resolution Integrated Spectroscopy), is an imager and spectrograph covering wavelengths from 0.365 to 1.05 μm. It has a field of view (FOV) of 7 × 7 arcmin for direct imaging, and 8 arcmin × 5.2 arcmin for low resolution spectroscopy. For spectroscopy, it offers tunable filters.^[9]

• EMIR: Espectrógrafo Multiobjeto Infra-Rojo (near-infrared multi-object spectrograph)

• MEGARA: Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía is an optical integral-field and multi-object spectrograph covering the visible light and near infrared wavelength range between 0.365 and 1 μm with a spectral resolution in the range R=6000–20000. The MEGARA IFU (also called the Large Compact Bundle, or LCB) offers a contiguous field of view of 12.5 arcsec x 11.3 arcsec, while the multi-object spectroscopy mode allows 92 objects to be observed simultaneously in a field of view of 3.5 arcmin x 3.5 arcmin by means of an equal number of robotic positioners. Both the LCB and MOS modes make use of 100 μm-core optical fibers (1267 in total) that are attached to a set of microlens arrays (with 623 spaxels in the case of the LCB and 92 x 7 in the case of the MOS) with each microlens covering an hexagonal region of 0.62 arcsec in diameter.^[10]

• HiPERCAM: High-speed optical camera

• CanariCam: is designed as a diffraction-limited imager. It is optimized as an imager, and although it offered a range of other observing modes, these did not compromise the imaging capability. CanariCam worked in the thermal infrared between approximately 7.5 and 25 μm. At the short-wavelength end, the cut-off was determined by the atmosphere—specifically atmospheric seeing. At the long wavelength end, the cut-off was determined by the detector; this loses sensitivity beyond around 24 μm, although the cut-off for individual detectors varied significantly. CanariCam was a very compact design. It was designed for a total weight of the cryostat and its on-telescope electronics to be under 400 kg.^{[citation needed]} Most previous mid-infrared instruments have used liquid helium as a cryogen; one of the requirements of CanariCam was that it should require no expensive and difficult to handle cryogens.^{[citation needed]}. CanariCam used a two-stage closed cycle cryocooler system to cool the cold optics and cryostat interior to approximately 28 K (−245 °C; −409 °F), and the detector itself to around 8 K (−265 °C; −445 °F), the temperature at which the detector worked most efficiently. CanariCam was decommissioned as of February 2021^[update].^[11]

• Other observatory sites
  • La Silla Observatory
  • Mauna Kea Observatories
  • Paranal Observatory
• Lists and comparisons
  • Extremely large telescope
  • List of largest optical reflecting telescopes
  • List of largest optical telescopes historically

Wikimedia Commons has media related to Gran Telescopio Canarias.

• Gran Telescopio Canarias
• GTC News
• Instituto de Astrofísica de Canarias (IAC)
• University of Florida CanariCam Archived 2016-11-24 at the Wayback Machine
• (in Spanish) Consejo Nacional de Ciencia y Tecnología de México
• (in Spanish) Instituto de Astronomía de la Universidad Nacional Autónoma de México
• CBC article—Giant Canary Islands telescope captures first light
• Images
• Gran Telescopo Canarias inauguration press dossier (in English)
• Merrifield, Michael. "Gran Telescopio Canarias". Deep Sky Videos. Brady Haran.