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The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) consists of astronomical cameras, telescopes and a computing facility that is surveying the sky for moving objects on a continual basis, including accurate astrometry and photometry of already detected objects. By detecting differences from previous observations of the same areas of the sky, it is expected to discover a very large number of new asteroids, comets, variable stars and other celestial objects. Its primary mission is to detect near-Earth objects that threaten impact events and is expected to create a database of all objects visible from Hawaii (three-quarters of the entire sky) down to apparent magnitude 24. Pan-STARRS is funded in large part by the United States Air Force through their Research Labs. Pan-STARRS NEO survey searches all the sky north of declination −47.5.〔https://twitter.com/astrokiwi/status/483572110179459073〕 The first Pan-STARRS telescope (PS1) is located at the summit of Haleakalā on Maui, Hawaii, and went online on December 6, 2008, under the administration of the University of Hawaii. PS1 began full-time science observations on May 13, 2010,〔(Pan-STARRS 1 Telescope Begins Science Mission )〕 and the PS1 Science Mission is underway, with operations funded by the PS1 Science Consortium, PS1SC, a consortium including the Max Planck Society in Germany, National Central University in Taiwan, Edinburgh, Durham and Queen's Belfast Universities in the UK, and Johns Hopkins and Harvard Universities in the United States and the Las Cumbres Observatory Global Telescope Network. Consortium observations for the all sky (as visible from Hawaii) survey were completed in April 2014. The Pan-STARRS Project is a collaboration between the University of Hawaii Institute for Astronomy, MIT Lincoln Laboratory, Maui High Performance Computing Center and Science Applications International Corporation. Telescope construction is funded by the U.S. Air Force. Having completed PS1, the Pan-STARRS Project is now focusing on building PS2, for which first light was achieved in 2013, with full science operations scheduled for 2014〔(Current status of Pan-STARRS and beyond )〕 and then the full array of four telescopes, sometimes called PS4. Completing the array of four telescopes is estimated at a total cost of US$100 million for the entire array.〔 As of mid-2014, PS2 was in the process of being commissioned.〔http://proceedings.spiedigitallibrary.org/data/Conferences/SPIEP/80055/91450Y.pdf〕 In the wake of substantial funding problems〔http://www.ifa.hawaii.edu/info/press-releases/Pan-STARRS_Donation/〕 no clear timeline existed for additional telescopes beyond the second. == Instruments == Pan-STARRS currently (2014) consists of two 1.8 m Ritchey-Chretien telescopes located at Haleakala in Hawaii. The initial telescope, PS1, saw first light using a low-resolution camera in June 2006. The telescope has a 3° field of view, which is extremely large for telescopes of this size, and is equipped with the largest digital camera ever built, recording almost 1.4 billion pixels per image. The focal plane has 60 separately mounted close packed CCDs arranged in an 8 × 8 array. The corner positions are not populated, because the optics do not illuminate the corners. Each CCD device, called an Orthogonal Transfer Array (OTA), has 4800 × 4800 pixels, separated into 64 cells, each of 600 × 600 pixels. This gigapixel camera or 'GPC' saw first light on August 22, 2007, imaging the Andromeda Galaxy. After initial technical difficulties that were later mostly solved, PS1 began full operation on May 13, 2010. Nick Kaiser, principal investigator of the Pan-STARRS project, summed it up saying “PS1 has been taking science-quality data for six months, but now we are doing it dusk-to-dawn every night.” (quote: June 15, 2010). The PS1 images however remain slightly less sharp than initially planned, which significantly affects some scientific uses of the data. Each image requires about 2 gigabytes of storage and exposure times will be 30 to 60 seconds (good enough to record objects down to apparent magnitude 22), with an additional minute or so used for computer processing. Since images will be taken on a continuous basis, it is expected that 10 Terabytes of data will be acquired by PS4 every night. Comparing against a database of known unvarying objects compiled from earlier observations will yield objects of interest: anything that has changed brightness and/or position for any reason. As of June 30/10 University of Hawaii in Honolulu received an $8.4 million contract modification under the PanSTARRS multi-year program to develop and deploy a telescope data management system for the project. At this time, all funds have been committed (FA9451-06-2-0338; P00008) The very large field of view of the telescope and the short exposure times enable approximately 6000 square degrees of sky to be imaged every night. The entire sky is 4π steradians, or 4π × (180/π)² ≈ 41,253.0 square degrees, of which about 30,000 square degrees are visible from Hawaii, which means that the entire sky can be imaged in a period of 40 hours (or about 10 hours per night on four days). Given the need to avoid times when the Moon is bright, this means that an area equivalent to the entire sky will be surveyed four times a month, which is entirely unprecedented. By the end of its initial three-year mission in April 2014, PS1 had imaged the sky 12 times in each of 5 filters (g,r,i,z,y). 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「Pan-STARRS」の詳細全文を読む スポンサード リンク
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