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〔}} |altitude = , top of pier〔〔 |weather = |wavelength = 320–1060 nm〔 |built = 2014–2019 (planned) |first_light = 2019〔 |website = |style = Three-mirror anastigmat, Paul-Baker / Mersenne-Schmidt wide-angle〔 |diameter = physical optical inner〔〔 |diameter2 = 3.420 m (1.800 m inner)〔 |diameter3 = 5.016 m (1.100 m inner)〔〔 |angular_resolution = 0.7″ median seeing limit 0.2″ pixel size〔 |area = 〔 |focal_length = 10.31 m (f/1.23) overall 9.9175 m (f/1.186) primary |mounting = altitude/azimuth |dome = }} The Large Synoptic Survey Telescope (LSST) is a wide-field survey reflecting telescope with an 8.4-meter primary mirror,〔〔 currently under construction, that will photograph the entire available sky every few nights.〔(LSST General Public FAQs )〕 The telescope uses a novel 3-mirror design which delivers sharp images over a very wide 3.5-degree diameter field of view, feeding a 3.2 gigapixel CCD imaging camera, the largest digital camera ever constructed.〔(【引用サイトリンク】title=Camera )〕 The telescope will be located on the El Peñón peak of Cerro Pachón, a 2,682 meter high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes. The LSST was the top-ranked large ground-based project in the 2010 Astrophysics Decadal Survey. The project officially began construction 1 August 2014 when the NSF authorized the FY2014 portion ($27.5 million) of its construction budget. The ceremonial laying of the first stone was performed on 14 April 2015. Site construction began on April 14, 2015, with engineering first light anticipated in 2019, science first light in 2021, and full operations for a ten-year survey commencing in January 2022.〔(LSST Project Schedule )〕 == Overview == The LSST design is unique among large telescopes (8 m-class primary mirrors) in having a very wide field of view: 3.5 degrees in diameter, or 9.6 square degrees. For comparison, both the Sun and the Moon, as seen from Earth, are 0.5 degrees across, or 0.2 square degrees. Combined with its large aperture (and thus light-collecting ability), this will give it a spectacularly large etendue of 319 m2∙degree2.〔 To achieve this very wide, undistorted field of view requires three mirrors, rather than the two used by most existing large telescopes: the primary mirror (M1) is in diameter, the secondary mirror (M2) is in diameter, and the tertiary mirror (M3), located in a large hole in the primary, is in diameter. The large hole reduces the primary mirror's light collecting area to , equivalent to a circle.〔 (Multiplying this by the field of view produces an etendue of 336 m2∙degree2; the actual figure is reduced by vignetting.) The primary and tertiary mirrors (M1 and M3) are being constructed as a single piece of glass, the "M1M3 monolith". A 3.2-gigapixel prime focus〔The camera is actually at the tertiary focus, not the prime focus, but being located at a "trapped focus" in front of the primary mirror, the associated technical problems are similar to those of a conventional prime-focus survey camera.〕 digital camera will take a 15-second exposure every 20 seconds.〔 Repointing such a large telescope (including settling time) within 5 seconds requires an exceptionally short and stiff structure. This in turn implies a very small f-number, which requires very precise focusing of the camera. Allowing for maintenance, bad weather and other contingencies, the camera is expected to take over 200,000 pictures (1.28 petabytes uncompressed) per year, far more than can be reviewed by humans. Managing and effectively data mining the enormous output of the telescope is expected to be the most technically difficult part of the project. Initial computer requirements are estimated at 100 teraflops of computing power and 15 petabytes of storage, rising as the project collects data. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Large Synoptic Survey Telescope」の詳細全文を読む スポンサード リンク
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