The Very Large Telescope is a telescope facility operated by the European Southern Observatory on Cerro Paranal in the Atacama Desert of northern Chile. The VLT consists of four individual telescopes, each with a primary mirror 8.2 m across, which are used separately but can be used together to achieve high angular resolution. The four separate optical telescopes are known as Antu, Kueyen and Yepun, which are all words for astronomical objects in the Mapuche language; the telescopes form an array, complemented by four movable Auxiliary Telescopes of 1.8 m aperture. The VLT operates at infrared wavelengths; each individual telescope can detect objects four billion times fainter than can be detected with the naked eye, when all the telescopes are combined, the facility can achieve an angular resolution of about 0.002 arc-second. In single telescope mode of operation angular resolution is about 0.05 arc-second. The VLT is the most productive ground-based facility for astronomy, with only the Hubble Space Telescope generating more scientific papers among facilities operating at visible wavelengths.
Among the pioneering observations carried out using the VLT are the first direct image of an exoplanet, the tracking of individual stars moving around the supermassive black hole at the centre of the Milky Way, observations of the afterglow of the furthest known gamma-ray burst. The VLT consists of an arrangement of four large telescopes with optical elements that can combine them into an astronomical interferometer, used to resolve small objects; the interferometer includes a set of four 1.8 meter diameter movable telescopes dedicated to interferometric observations. The first of the UTs started operating in May 1998 and was offered to the astronomical community on 1 April 1999; the other telescopes became operational in 2000, enabling multi-telescope VLT capability. Four 1.8-metre Auxiliary Telescopes have been added to the VLTI to make it available when the UTs are being used for other projects. These ATs were installed and became operational between 2004 and 2007; the VLT's 8.2-meter telescopes were designed to operate in three modes: as a set of four independent telescopes. as a single large coherent interferometric instrument, for extra resolution.
This mode is used for observations of bright sources with small angular extent. As a single large incoherent instrument, for extra light-gathering capacity; the instrumentation required to obtain a combined incoherent focus was not built. In 2009, new instrumentation proposals were put forward to make that observing mode available. Multiple telescopes are sometimes independently pointed at the same object, either to increase the total light-gathering power or to provide simultaneous observations with complementary instruments; the UTs are equipped with a large set of instruments permitting observations to be performed from the near-ultraviolet to the mid-infrared, with the full range of techniques including high-resolution spectroscopy, multi-object spectroscopy and high-resolution imaging. In particular, the VLT has several adaptive optics systems, which correct for the effects of atmospheric turbulence, providing images as sharp as if the telescope were in space. In the near-infrared, the adaptive optics images of the VLT are up to three times sharper than those of the Hubble Space Telescope, the spectroscopic resolution is many times better than Hubble.
The VLTs are noted for their high level of observing automation. The 8.2 m-diameter telescopes are housed in compact, thermally controlled buildings, which rotate synchronously with the telescopes. This design minimises any adverse effects on the observing conditions, for instance from air turbulence in the telescope tube, which might otherwise occur due to variations in the temperature and wind flow; the principal role of the main VLT telescopes is to operate as four independent telescopes. The interferometry is used about 20 percent of the time for high-resolution on bright objects, for example, on Betelgeuse; this mode allows astronomers to see details up to 25 times finer than with the individual telescopes. The light beams are combined in the VLTI using a complex system of mirrors in tunnels where the light paths must be kept equal within differences of less than 1/1000 mm over a light path of a hundred metres. With this kind of precision the VLTI can reconstruct images with an angular resolution of milliarcseconds.
It had long been ESO's intention to provide "real" names to the four VLT Unit Telescopes, to replace the original technical designations of UT1 to UT4. In March 1999, at the time of the Paranal inauguration, four meaningful names of objects in the sky in the Mapuche language were chosen; this indigenous people lives south of Santiago de Chile. An essay contest was arranged in this connection among schoolchildren of the Chilean II Region of which Antofagasta is the capital to write about the implications of these names, it drew many entries dealing with the cultural heritage of ESO's host country. The winning essay was submitted by 17-year-old Jorssy Albanez Castilla from Chuquicamata near the city of Calama, she received an amateur telescope, during the inauguration of the Paranal site. Unit Telescopes 1–4 are since known as Antu, Kueyen and Yepun, respectively. There was some confusion as to whether Yepun stands for the evening star Venus, beca
The Starr carbine was a breechloading single-shot rifle used by the United States Army. Designed in 1858, the Starr was used by cavalry soldiers in the American Civil War. In January 1858, Ebenzer Starr submitted his design for a single-shot, breech-loading rifle to the Washington Armory for evaluation. During testing, the rifle was noted to have no misfires, its accuracy was considered better than average. Testers commented that if the gas seal could be improved, the weapon would be better than its rival, the Sharps carbine; the rifle was adopted as the Model 1858 carbine. Between 1861 and 1864, over 20,000 were produced by the Starr Arms Company of New York; the Model 1858 was designed to fire linen cartridges. In 1865, the government ordered; these proved to be successful, an additional 2,000 were ordered. Although the Starr carbine had proven to be effective during the Civil War, it was not successful during the trials of 1865 by the U. S. Army trials board, no further rifles were ordered. During the war, the Starr Arms Company had been the fifth largest supplier of carbines and the third largest supplier of.44 caliber single action pistols.
After the war had ended, with no further government contracts, Starr could no longer compete with larger manufacturers like Winchester and Colt, the company closed its doors in 1867. The Starr carbine was similar in design to the Sharps carbine; the Starr had a longer receiver and a distinctive web between the tail of the breech lever and the underside of the butt. The Starr carbine had a.54 caliber barrel, 21 inches in length. The weapon had a weight of 7.4 lbs. A bayonet could not be fitted; the Starr carbine had a three-position rear sight composed of a standing block and two folding leaves. The Starr carbine fired linen cartridges that were ignited by conventional percussion caps; the weapon fired reliably. The Starr carbine was produced in two versions, the Model 1858 and the Model 1865; the Model 1858 could fire linen or paper cartridges made by Starr, could fire similar cartridges made for the Sharps carbine. The Model 1865 version fired the metal 56-50 Spencer rimfire cartridge, as a result, had a redesigned hammer and breech block
Pepkor is a South African based investment and holding company with business interests in Africa, United Kingdom, Romania and New Zealand. It manages a portfolio of retail chains focused on the value market selling predominantly clothing and textiles, its main operating subsidiaries are Pep and Ackermans in South Africa and Best & Less in Australia, all based on a high volume/lower margin business model. Formally known as PEP stores the company changed its name to Pepkor Limited in 1982 and PEP stores became a subsidiary company. In 2011 Pepkor's chairman Christo Wiese was ranked as the 782nd richest person in the world on Forbes's list of the world's 1210 billionaires with an estimated net worth of US$1,6bn. In 2011 private equity company Brait bought a 24,6% stake in Pepkor for R4,18bn, valuing the company at about R17bn. Pepkor aims to expand its presence in the rest of Africa by opening 50 stores in Nigeria. In 2014 Christo Wiese sold Pepkor to Steinhoff International in exchange for about 20% of Steinhoff's issued shares.
PEP retail stores focus on selling clothing, textiles, home ware and cellular products to the lower end of the market that aims to sell items at the lowest possible price in large volumes in both rural and urban areas. They are Pepkor's largest and first subsidiary with over 1,500 stores in countries across southern Africa. Ackermans focuses on selling clothing and household textiles to the middle market from 374 stores across South Africa. Ackermans subsidiary Jay Jays, based upon the Australian brand of the same name focuses on selling the same type of products in the middle market segment in high volumes and at low prices in the South African market from its 62 stores. Jay Jays in South Africa is a joint venture between Pepkor and Jay Jay's Australian parent company, Just Group. Pepkor acquired the Australian retail chain in 1998 at the start of a strong period of growth for subsidiary over a seven-year period during which it doubled in size; the chain has 191 stores across Australia adhering to Pepkor's business model of selling textiles in high volumes and low prices.
Dunns focuses on selling adult clothing and accessories to the middle income market from its 266 stores across southern Africa. Its model is to sell high volumes at low cost but to sell these items from stores based in shopping centres and malls. Shoe City focuses on selling footwear from 86 stores in South Africa. Like most Pepkor subsidiaries it focuses on selling to the mid-market segment of the retail industry in large volumes at low prices. Pepco is Pepkor's first major investment in continental Europe, its business model focuses on offering cash-based discounts on clothing and houseware items to the lower income middle class segment of the market in small to medium-sized towns across Poland. In April 2014, the company had 27 stores in Slovakia; as of November 2018, the company has 204 stores in Romania. John Craig is a retail chain with 56 stores and 327 employees in South Africa that sells top quality men's branded apparel and accessories, its target market is middle income South Africans with a Middle Living Standards Measure rating of between 5 and 8.
Postie Plus has 65 retail clothing stores in New Zealand, is Pepkor's first investment in New Zealand, purchasing Postie Plus after it was put into voluntary administration in 2014. Companiesandmarkets.com - PEPKOR LTD: Company Financials and Credit Information Business Times: It's show or go for MDs of Pepkor chains