Schott AG is an international manufacturing group of glass and glass-ceramics. The company is headquartered in Mainz and employs approximately 15,000 people worldwide, all shares of Schott AG are solely held by the Carl Zeiss Foundation. The company reported sales worth 1.93 billion Euros in its fiscal year 2014/2015, Erich Schott, the son of the company founder, took over the management of the plant in 1927. The company suffered a blow at the end of World War II. After the main plant in Jena was expropriated, Erich Schott opened a new plant in Mainz. After the fall of the inner German border in 1989, the based in Mainz acquired the East German company in Jena. In 2008, Schott announced that it planned to produce crystalline photovoltaic cells and it planned to produce thin-film PV wafers with a capacity of 100 MW. They had already been making 15 MW of photovoltaics annually in Billerica, the company started operating in China since 2011, with a large production
The larger the objective, the more light the telescope collects and the finer detail it resolves. People use telescopes and binoculars for activities such as astronomy, ornithology and reconnaissance. The telescope is more a discovery of optical craftsmen than an invention of a scientist and it is in the Netherlands in 1608 where the first recorded optical telescopes appeared. The invention is credited to the spectacle makers Hans Lippershey and Zacharias Janssen in Middelburg, galileo greatly improved on these designs the following year, and is generally credited as the first to use a telescope for astronomy. Galileos telescope used Hans Lippersheys design of an objective lens and a concave eye lens. Johannes Kepler proposed an improvement on the design used a convex eyepiece. For reflecting telescopes, which use a mirror in place of the objective lens. The theoretical basis for curved mirrors behaving similar to lenses was probably established by Alhazen, the late 20th century has seen the development of adaptive optics and space telescopes to overcome the problems of astronomical seeing.
The basic scheme is that the primary light-gathering element the objective and this image may be recorded or viewed through an eyepiece, which acts like a magnifying glass. The eye sees an inverted magnified virtual image of the object, most telescope designs produce an inverted image at the focal plane, these are referred to as inverting telescopes. In fact, the image is both turned upside down and reversed left to right, so that altogether it is rotated by 180 degrees from the object orientation, in astronomical telescopes the rotated view is normally not corrected, since it does not affect how the telescope is used. However, a diagonal is often used to place the eyepiece in a more convenient viewing location, and in that case the image is erect. In terrestrial telescopes such as spotting scopes and binoculars, There are telescope designs that do not present an inverted image such as the Galilean refractor and the Gregorian reflector. These are referred to as erecting telescopes, many types of telescope fold or divert the optical path with secondary or tertiary mirrors.
These may be part of the optical design, or may simply be used to place the eyepiece or detector at a more convenient position. Telescope designs may use specially designed additional lenses or mirrors to improve image quality over a field of view. Design specifications relate to the characteristics of the telescope and how it performs optically, several properties of the specifications may change with the equipment or accessories used with the telescope, such as Barlow lenses, star diagonals and eyepieces. These interchangeable accessories dont alter the specifications of the telescope, however they alter the way the telescopes properties function, typically magnification, angular resolution and FOV
The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods through its subsequent large-scale evolution. If the known laws of physics are extrapolated to the highest density regime, detailed measurements of the expansion rate of the universe place this moment at approximately 13.8 billion years ago, which is thus considered the age of the universe. After the initial expansion, the universe cooled sufficiently to allow the formation of subatomic particles, giant clouds of these primordial elements coalesced through gravity in halos of dark matter, eventually forming the stars and galaxies visible today. Since Georges Lemaître first noted in 1927 that a universe could be traced back in time to an originating single point. More recently, measurements of the redshifts of supernovae indicate that the expansion of the universe is accelerating, the known physical laws of nature can be used to calculate the characteristics of the universe in detail back in time to an initial state of extreme density and temperature.
American astronomer Edwin Hubble observed that the distances to faraway galaxies were strongly correlated with their redshifts, assuming the Copernican principle, the only remaining interpretation is that all observable regions of the universe are receding from all others. Since we know that the distance between galaxies increases today, it must mean that in the past galaxies were closer together, the continuous expansion of the universe implies that the universe was denser and hotter in the past. Large particle accelerators can replicate the conditions that prevailed after the early moments of the universe, resulting in confirmation, these accelerators can only probe so far into high energy regimes. Consequently, the state of the universe in the earliest instants of the Big Bang expansion is still poorly understood, the first subatomic particles to be formed included protons and electrons. Though simple atomic nuclei formed within the first three minutes after the Big Bang, thousands of years passed before the first electrically neutral atoms formed, the majority of atoms produced by the Big Bang were hydrogen, along with helium and traces of lithium.
Giant clouds of primordial elements coalesced through gravity to form stars and galaxies. The framework for the Big Bang model relies on Albert Einsteins theory of relativity and on simplifying assumptions such as homogeneity. The governing equations were formulated by Alexander Friedmann, and similar solutions were worked on by Willem de Sitter, extrapolation of the expansion of the universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past. This singularity indicates that general relativity is not a description of the laws of physics in this regime. How closely models based on general relativity alone can be used to extrapolate toward the singularity is debated—certainly no closer than the end of the Planck epoch. This primordial singularity is itself called the Big Bang, but the term can refer to a more generic early hot. The agreement of independent measurements of this age supports the model that describes in detail the characteristics of the universe.
The earliest phases of the Big Bang are subject to much speculation, in the most common models the universe was filled homogeneously and isotropically with a very high energy density and huge temperatures and pressures and was very rapidly expanding and cooling
An equatorial mount is a mount for instruments that compensate the rotation of earth by having one rotational axis parallel to the Earths axis of rotation. This type of mount is used for astronomical telescopes and cameras, such an arrangement is called a sidereal drive. In astronomical telescope mounts, the axis is paired with a second perpendicular axis of motion. They may be equipped with setting circles to allow for the location of objects by their celestial coordinates, equatorial mounts differ from mechanically simpler altazimuth mounts, which require variable speed motion around both axes to track a fixed object in the sky. Equatorial telescope mounts come in many designs, in the last twenty years motorized tracking has increasingly been supplemented with computerized object location. Digital setting circles take a computer with an object database that is attached to encoders. The computer monitors the telescopes position in the sky, the operator must push the telescope. Go-to systems use servo motors and the operator need not touch the instrument at all to change its position in the sky.
The computers in these systems are typically either hand-held in a paddle or supplied through an adjacent laptop computer which is used to capture images from an electronic camera. The electronics of modern telescope systems often include a port for autoguiding, a special instrument tracks a star and makes adjustment in the telescopes position while photographing the sky. To do so the autoguider must be able to issue commands through the control system. These commands can compensate for very slight errors in the tracking performance, in new observatory designs, equatorial mounts have been out of favor for decades in large-scale professional applications. Massive new instruments are most stable when mounted in an alt-azimuth configuration, computerized tracking and field-derotation are not difficult to implement at the professional level. At the amateur level, equatorial mounts remain popular, in the German equatorial mount, the primary structure is a T-shape, where the lower bar is the right ascension axis, and the upper bar is the declination axis.
The telescope is placed on one end of the axis. The right ascension axis has bearings below the T-joint, that is, the Open Fork mount has a Fork attached to a right ascension axis at its base. The telescope is attached to two points at the other end of the fork so it can swing in declination. Most modern mass-produced catadioptric reflecting telescopes tend to be of this type, the mount resembles an Altazimuth mount, but with the azimuth axis tilted and lined up to match earth rotation axis with a piece of hardware usually called a wedge
California Institute of Technology
The California Institute of Technology is a private doctorate-granting university located in Pasadena, United States. The vocational and preparatory schools were disbanded and spun off in 1910, the university is one among a small group of Institutes of Technology in the United States which is primarily devoted to the instruction of technical arts and applied sciences. Caltech has six divisions with strong emphasis on science and engineering, managing $332 million in 2011 in sponsored research. Its 124-acre primary campus is located approximately 11 mi northeast of downtown Los Angeles, first-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at Caltech. Although Caltech has a tradition of practical jokes and pranks. The Caltech Beavers compete in 13 intercollegiate sports in the NCAA Division IIIs Southern California Intercollegiate Athletic Conference, Caltech is frequently cited as one of the worlds best universities. There are 112 faculty members who have elected to the United States National Academies.
In addition, numerous faculty members are associated with the Howard Hughes Medical Institute as well as NASA, according to a 2015 Pomona College study, Caltech ranked number one in the U. S. for the percentage of its graduates who go on to earn a PhD. Caltech started as a school founded in Pasadena in 1891 by local businessman and politician Amos G. Throop. The school was known successively as Throop University, Throop Polytechnic Institute, the vocational school was disbanded and the preparatory program was split off to form an independent Polytechnic School in 1907. At a time when research in the United States was still in its infancy, George Ellery Hale. He joined Throops board of trustees in 1907, and soon began developing it and he engineered the appointment of James A. B. Scherer, a literary scholar untutored in science but a capable administrator and fund raiser, scherer persuaded retired businessman and trustee Charles W. Gates to donate $25,000 in seed money to build Gates Laboratory, the first science building on campus.
In 1910, Throop moved to its current site, arther Fleming donated the land for the permanent campus site. The promise of Throop attracted physical chemist Arthur Amos Noyes from MIT to develop the institution and assist in establishing it as a center for science, with the onset of World War I, Hale organized the National Research Council to coordinate and support scientific work on military problems. This institution, with its able investigators and excellent research laboratories, through the National Research Council, Hale simultaneously lobbied for science to play a larger role in national affairs, and for Throop to play a national role in science. During the course of the war, Hale and Millikan worked together in Washington on the NRC, they continued their partnership in developing Caltech. Under the leadership of Hale and Millikan, Caltech grew to prominence in the 1920s
Gran Telescopio Canarias
Construction of the telescope, sited on a volcanic peak 2,267 metres above sea level, took seven years and cost €130 million. Its installation had been hampered by weather conditions and the difficulties of transporting equipment to such a remote location. First light was achieved in 2007 and scientific observations began in 2009, planning for the construction of the telescope, which started in 1987, involved more than 1,000 people from 100 companies. As of 2015, it is the worlds largest single-aperture optical telescope, the distribution of the availability of time to use the telescope meets its financial structure, 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, 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. Its Day One instrumentation was OSIRIS, scientific observations began properly in May 2009.
The Gran Telescopio Canarias formally opened its shutters on July 24,2009, more than 500 astronomers, government officials and journalists from Europe and the Americas attended the ceremony. The University of Floridas CanariCam is a mid-infrared imager with spectroscopic and polarimetric capabilities, in the future, when the Cassegrain focus of the telescope is commissioned, it is expected that CanariCam will move to this focus, which will provide superior performance with the instrument. CanariCam is designed as a diffraction-limited imager and it is optimised as an imager, and although it will offer a range of other observing modes, these will not compromise the imaging capability. The fact that CanariCam offers polarimetry and coronagraphy in addition to the more standard imaging and spectroscopic modes makes it a versatile, CanariCam will work in the thermal infrared between ≈7.5 and 25 μm. At the short end the cut-off is determined by the atmosphere. At the long wavelength end the cut-off is determined by the detector, CanariCam is a very compact design.
It is expected that the weight of the cryostat and its on-telescope electronics will be under 400 kg. Most previous mid-infrared instruments have used liquid helium as a cryogen, one of the requirements of CanariCam is that it should require no expensive, CanariCam is expected to be installed in 2010. The IACs OSIRIS, is an imaging and low resolution spectrograph with longslit and multiobject spectroscopic modes. It covers the range from 0.365 to 1.05 µm with a field of views of 7 ×7 arcmin. It provides a new generation of instrumental observation techniques such as the tunable filters, the charge-shuffling capability in the CCD detectors, etc. Gran Telescopio Canarias
Without active optics, the construction of 8 metre class telescopes is not possible, nor would telescopes with segmented mirrors be feasible. Active optics is not to be confused with adaptive optics, which operates at a shorter timescale, most modern telescopes are reflectors, with the primary element being a very large mirror. Historically, primary mirrors were quite thick in order to maintain the correct figure in spite of forces tending to deform it, like wind. This limited their maximum diameter to 5 or 6 metres, such as Palomar Observatorys Hale telescope, a new generation of telescopes built since the 1980s use thin, lighter weight mirrors instead. They are too thin to maintain themselves rigidly in the correct shape, the actuators apply variable forces to the mirror body to keep the reflecting surface in the correct shape over repositioning. The telescope may be segmented into multiple smaller mirrors, which reduce the sagging due to weight that occurs for large, the combination of actuators, an image quality detector, and a computer to control the actuators to obtain the best possible image, is called active optics.
The name active optics means that the system keeps a mirror in its optimal shape against environmental forces such as wind, thermal expansion, Active optics compensate for distorting forces that change relatively slowly, roughly on timescales of seconds. The telescope is therefore actively still, in its optimal shape, Active optics should not be confused with adaptive optics, which operates on a much shorter timescale to compensate for atmospheric effects, rather than for mirror deformation. The influences that active optics compensate are intrinsically slower and have an amplitude in aberration. Adaptive optics on the other hand corrects for atmospheric distortions that affect the image at 100–1000 Hz and these corrections need to be much faster, but have smaller amplitude. Because of this, adaptive optics uses smaller corrective mirrors and this used to be a separate mirror not integrated in the telescopes light path, but nowadays this can be the second, third or fourth mirror in a telescope.
Complicated laser set-ups and interferometers can be actively stabilized, the system can be sped up or made more noise-immune by using a PID controller. For pulsed lasers the controller should be locked to the repetition rate, a continuous pilot beam can be used to allow for up to 10 kHz bandwidth of stabilization for low repetition rate lasers. Sometimes Fabry–Pérot interferometers have to be adjusted in length to pass a given wavelength, the reflected light is extracted by means of a Faraday rotator and a polarizer. Long optical cavities are very sensitive to the mirror alignment, a control circuit can be used to peak power. One possibility is to perform small rotations with one end mirror, if this rotation is about the optimum position, no power oscillation occurs. Any beam pointing oscillation can be removed using the steering mechanism mentioned above. X-ray active optics, using actively deformable grazing incidence mirrors, are being investigated, adaptive optics – faster technology for smaller aberrations
Thirty Meter Telescope
While construction of the telescope was set to resume on April 2 and on June 24,2015, it was blocked by further protests each time. Roque de los Muchachos Observatory, La Palma, Canary Islands, the TMT would become the last area on Mauna Kea on which any telescope will ever be built. Scientists have been considering ELTs since the mid 1980s, in 2000, astronomers considered the possibility of a telescope with a light-gathering mirror larger than 20 meters in diameter. The US National Academy of Sciences recommended a 30-meter telescope be the focus of U. S. interests, the TMT is designed for near-ultraviolet to mid-infrared observations, featuring adaptive optics to assist in correcting image blur. The TMT will be at the highest altitude of all the proposed ELTs, the telescope has government-level support from several R&D spending nations, Japan and India. In 2000, astronomers began considering the potential of larger than 20 meters in diameter. Two technologies were considered, segmented mirrors like that of the Keck Observatory, the US National Academy of Sciences made a suggestion that a 30-meter telescope should be the focus of US astronomy interests and recommended it to be built within the decade.
The University of California, along with Caltech began development of a 30-meter telescope that same year, the California Extremely Large Telescope began development along with the Giant Magellan Telescope, the Giant Segmented Mirror Telescope and the Very Large Optical Telescope. These studies would become the Thirty Meter Telescope. The TMT would have nine times the area of the older Keck telescope using slightly smaller mirror segments in a vastly larger group. Another telescope of a diameter in the works is the European Extremely Large Telescope being built in northern Chile. The telescope is designed for observations from near-ultraviolet to mid-infrared, in addition, its adaptive optics system will help correct for image blur caused by the atmosphere of the Earth, helping it to reach the potential of such a large mirror. Among existing and planned ELTs, the TMT will have the highest altitude, both use segments of small 1.44 m hexagonal mirrors—a design vastly different from the large mirrors of the Large Binocular Telescope or the Giant Magellan Telescope.
The TMT has government-level support from two large R&D spending nations and Japan, as well as other top R&D ones, including Canada, the United States is contributing some funding, but less than the formal partnership. On July 21,2009 the TMT board announced Mauna Kea as the preferred site, the final TMT site selection decision was based on a combination of scientific and political criteria. Chile is where the European Southern Observatory is building the E-ELT, if both next-generation telescopes were in the same hemisphere, there would be many astronomical objects that neither could observe. The telescope was given approval by the state Board of Land, the Hawaii Board of Land and Natural Resources conditionally approved the Mauna Kea site for the TMT in February 2011. The approval has been challenged, the Board officially approved the following a hearing on February 12,2013
President Dwight D. Eisenhower established NASA in 1958 with a distinctly civilian orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29,1958, disestablishing NASAs predecessor, the new agency became operational on October 1,1958. Since that time, most US space exploration efforts have led by NASA, including the Apollo Moon landing missions, the Skylab space station. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle, the agency is responsible for the Launch Services Program which provides oversight of launch operations and countdown management for unmanned NASA launches. NASA shares data with various national and international such as from the Greenhouse Gases Observing Satellite. Since 2011, NASA has been criticized for low cost efficiency, from 1946, the National Advisory Committee for Aeronautics had been experimenting with rocket planes such as the supersonic Bell X-1.
In the early 1950s, there was challenge to launch a satellite for the International Geophysical Year. An effort for this was the American Project Vanguard, after the Soviet launch of the worlds first artificial satellite on October 4,1957, the attention of the United States turned toward its own fledgling space efforts. This led to an agreement that a new federal agency based on NACA was needed to conduct all non-military activity in space. The Advanced Research Projects Agency was created in February 1958 to develop technology for military application. On July 29,1958, Eisenhower signed the National Aeronautics and Space Act, a NASA seal was approved by President Eisenhower in 1959. Elements of the Army Ballistic Missile Agency and the United States Naval Research Laboratory were incorporated into NASA, earlier research efforts within the US Air Force and many of ARPAs early space programs were transferred to NASA. In December 1958, NASA gained control of the Jet Propulsion Laboratory, NASA has conducted many manned and unmanned spaceflight programs throughout its history.
Some missions include both manned and unmanned aspects, such as the Galileo probe, which was deployed by astronauts in Earth orbit before being sent unmanned to Jupiter, the experimental rocket-powered aircraft programs started by NACA were extended by NASA as support for manned spaceflight. This was followed by a space capsule program, and in turn by a two-man capsule program. This goal was met in 1969 by the Apollo program, reduction of the perceived threat and changing political priorities almost immediately caused the termination of most of these plans. NASA turned its attention to an Apollo-derived temporary space laboratory, to date, NASA has launched a total of 166 manned space missions on rockets, and thirteen X-15 rocket flights above the USAF definition of spaceflight altitude,260,000 feet. The X-15 was an NACA experimental rocket-powered hypersonic research aircraft, developed in conjunction with the US Air Force, the design featured a slender fuselage with fairings along the side containing fuel and early computerized control systems
Zerodur, a registered trademark of Schott AG, is a lithium-aluminosilicate glass-ceramic produced by Schott AG since 1968. It has been used for a number of large telescope mirrors including Keck I, Keck II. With its very low coefficient of expansion it can be used to produce mirrors that retain acceptable figures in extremely cold environments such as deep space. Although it has advantages for applications requiring a coefficient of thermal expansion less than that of borosilicate glass, the tight tolerance on CTE, ±0. 007×10−6 K−1, allows highly accurate applications that require high-precision. Zerodur has both a component and a crystalline component. Its most important properties are, Particularly low thermal expansion, in the range 0 to 50 °C it has a mean of 0 ±0. 007×10−6 K−1, high 3D homogeneity with few inclusions and internal stria. Hardness similar to glass, so that it can be ground. Good chemical stability similar to that of fused quartz
A telescope mount is a mechanical structure which supports a telescope. Telescope mounts are designed to support the mass of the telescope, many sorts of mounts have been developed over the years, with the majority of effort being put into systems that can track the motion of the stars as the Earth rotates. Fixed-altitude mounts usually have the primary optics fixed at an angle while rotating horizontally. They can cover the sky but only observe objects for the short time when that object passes a specific altitude. Transit mounts are single axis mounts fixed in azimuth while rotating in altitude and this allows the telescope to view the whole sky, but only when the Earths rotation allows the objects to cross through that narrow north-south line. This type of mount is used in Transit telescopes, designed for precision astronomical measurement, Transit mounts are used to save on cost or where the instruments mass makes movement on more than one axis very difficult, such as large radio telescopes.
Altazimuth, altitude-azimuth, or alt-az mounts allow telescopes to be moved in altitude, or azimuth and this meant until recently it was normally used with inexpensive commercial and hobby constructions. Since the invention of digital tracking systems, altazimuth mounts have come to be used in all modern large research telescopes. Digital tracking has made it a popular telescope mount used in amateur astronomy, besides the mechanical inability to easily follow celestial motion the altazimuth mount does have other limitations. The mount has blind spot or zenith hole, a spot near the zenith where the rate in the azimuth coordinate becomes too high to accurately follow equatorial motion. These mounts require a third axis to de-rotate the field as the telescope tracks, alt-alt mounts, or altitude-altitude mounts, are designs similar to horizontal equatorial yoke mounts or Cardan suspension gimbals. This mount is an alternative to the mount that has the advantage of not having a blind spot near the zenith.
It has the disadvantage of having all the mass and these mounts may include a third azimuth axis to rotate the entire mount into an orientation that allows smoother tracking. Slewing or mechanically driving the mounts polar axis in a direction to the Earths rotation allows the telescope to accurately follow the motion of the night sky. Tilting the polar axis adds a level of complexity to the mount, mechanical systems have to be engineered to support one or both ends of this axis. Designs such as German equatorial or cross axis mounts need large counter weights to counterbalance the mass of the telescope, larger domes and other structures are needed to cover the increased mechanical size and range of movement of equatorial mounts. Because of this, equatorial mounts become less viable in very large telescopes and have been pretty much replaced by altazimuth mounts for those applications, instead of the classical mounting using two axles, the mirror is supported by six extendable struts. This configuration allows moving the telescope in all six degrees of freedom