In 1837, Wilhelm Beer and Johann Heinrich Modler discussed the benefits of an observatory on the Moon. In 1946, the American theoretical astrophysicist Lyman Spitzer suggested a telescope in space 11 years before the Soviet Union published the first satellite Sputnik 1. Spitzer’s proposal for a large telescope that would not be obstructed by the Earth’s atmosphere. After lobbying for such a system to be built in the 1960s and 70s, Spitzer’s vision was ultimately turned into the Hubble Space Telescope, launched on 24 April 1990 by Space Shuttle Discovery (STS-31).
HistoryThe James Webb Space Telescope (JWST or “Webb”) is a space telescope to be the successor to the Hubble Space Telescope. The JWST will provide greatly improved resolution and precision compared to Hubble, and will allow a wide range of research in astronomy and cosmology. One of its main objectives is to notice some of the most distant events and objects in the universe, such as the formation of the first galaxies.
Such goals are beyond reaching existing ground and area-based tools. Other goals incriminate understanding the formation of stars and planets, and direct visualization of exoplanets and novels. The Optical Telescope Element, the main mirror of JWST, consists of 18 hexagonal mirror sections made of gold-plated beryllium. They are connected to create a 6.5-meter (21 ft 4-inch; 260-inch) mirror that is much larger than the 2.4-meter (7 ft 10-inch; 94-inch) mirror of Hubble. Unlike the Hubble observed in near ultraviolet, visible, and near infrared (0.1 to 1 јm) spectra, JWST will observe the long wavelength of visible light in a lower frequency range from medium infrared (0.
6 to 27 јm). This will allow JWST to observe high red shift objects that are so old and slight that Hubble and other previous instruments cannot observe. The telescope must be kept extremely cold to observe on the infrared without interference, so Earth-Sun L2 should be deployed in an area close to the Lagrangian point. Under K (20220 ° C; €’370 ° F).JWST is being grew by NASA – with the significant contribution of the Canadian Space Agency and the European Space Agency – and from 1961 to 1968, named after NASA’s director, the US state official, James E. Webb. An integral part of the Apollo program. The development began in 1996, but the project has undergone numerous delays and cost overruns and in 2005 a major redesign. The construction of JWST was completed in late 2016, and then the comprehensive testing phase began. In March 2018, NASA delayed the launch of the JWST after the telescope ripped during the sun delivery deployment.The launch of JWST was postponed again in June 2018 following the recommendations of an independent review committee and is currently scheduled for March 2021. Overview In 1996, JWST emerged as the Next Generation Space Telescope (NGST). In 2002, NASA’s second director (1961 olarak1968) changed the name of James E. Webb (1906-1992), noting that he played an important role in the Apollo program and conducted scientific research as a major NASA activity. United States created an agency and gave the name JWST, the National Aeronautics and Space Administration, in working with the European Space Agency and the Canadian Space Agency.The telescope has a mass of about half the demanded mass of the Hubble Space Telescope, but its primary mirror is about five times larger (25 m2 or 270 mІ or 4.5 m2 or 48 sq ft) than the gold-coated beryllium reflector (6.5 meters in diameter). JWST is for near-infrared astronomy, The device can also see red and orange visible lights. The design emphasizes the mid-infrared proximity for three main reasons: The visible emissions of high red translational objects ensure strong diffusion of cold objects such as infrared, slip disks and planet within the infrared, and this strip is difficult to examine. with existing space telescopes such as Earth or Hubble. Ground-based telescopes should look at the atmosphere, which is opaque in many infrared bands (see atmospheric transmission pattern). Even where the atmosphere is transparent, many of the target chemical compounds such as water, carbon dioxide and methane perform very complex analyzes in the Earth’s atmosphere. Being space telescopes, such as Hubble, are not cold enough (the Hubble mirror is held at about 15 ° C (288 K)), and therefore the bands cannot work because the telescope is strongly emitted in the infrared strips. The Hubble mirror is held at about 15 ° C (288 K), and therefore the bands cannot work because the telescope is strongly spread in infrared bands. Existing space telescopes such as Dubble are not cold enough (Hubble mirror at approximately 15 ° C (288 K) and the telescope is cannot function to work due to its strong spreading in infrared strips. The JWST will run approximately 1,500,000 km (930,000 miles) from Earth’s orbit, near the Earth-Sun L2 (Lagrange) point. By comparison, Hubble is orbited by over 550 kilometers (340 mi) of Earth’s surface, and the Moon is roughly 400,000 kilometers (250,000 mi) from Earth. This distance makes it almost impossible to repair after the launch or to upgrade the JWST equipment. Objects located near this point may allow the Sun to synchronize with the Earth, allowing the telescope to stay at a roughly constant distance and use a single sunshade to prevent heat and light from the Sun and Earth. This will keep the spacecraft temperature below 50 K (olan220 ° C; ,370 ° F) necessary for infrared observations. The principal contractor is Northrop Grumman. Sunshield ProtectionTo make observations in the infrared spectrum, the JWST must be kept very cold (below 50 K (° 220 ° C; 70370 ° F)), otherwise it will cause the infrared radiation to be played from the telescope itself. Therefore, the Sun uses a great sunscreen to prevent light and heat from the Earth and Moon, and the Earth-Sun position near the L2 point ensures that all three bodies are always on the same side of the spacecraft. The halo trajectory around L2 avoids the shadow of Earth and the Moon and provides a stable environment for sunscreen and solar panels.  The display provides a constant temperature throughout the structures on the dark side and is critical in ensuring the precise alignment of the primary mirror parts.The five-layer sunshade is made of polyimide film with silicon-coated membranes on one side and aluminum-coated on one side. Accidental tearing of the sensitive film structure during the test is a factor that delays the project. Since the sun visor is designed to fold twelve times, the Ariane 5 rocket will fit into the 4.57 m (5 yard) — 16.19 m (17.7 yard) transport area. When placed at point L2, 21.197 m (23.18 yards) — 14.162 m (15.55 yards) will be opened. The sunshade was manually mounted in ManTech (NeXolve) in Huntsville, Alabama, before being delivered to Northrop Grumman in Redondo Beach, California before being tested. OpticsTo make observations in the infrared spectrum, the JWST must be kept very cold (below 50 K (° 220 ° C; 70370 ° F)), otherwise it will cause the infrared radiation to be played from the telescope itself. Therefore, the Sun uses a great sunscreen to prevent light and heat from the Earth and Moon, and the Earth-Sun position near the L2 point ensures that all three bodies are always on the same side of the spacecraft. The halo trajectory around L2 avoids the shadow of Earth and the Moon and provides a stable environment for sunscreen and solar panels. The display provides a constant temperature throughout the structures on the dark side and is critical in ensuring the precise alignment of the primary mirror parts. The five-layer sunshade is made of polyimide film with silicon-coated membranes on one side and aluminum-coated on the other. Accidental tearing of the sensitive film structure during the test is a factor that delays the project. Since the sun visor is designed to be folded up to twelve times, the Ariane 5 rocket will fit into the 4.57 m (5 yard) — 16.19 m (17.7 yard) transport area. When placed at point L2, 21.197 m (23.18 yards) — 14.162 m (15.55 yards) will be opened. The sunshade was manually mounted in ManTech (NeXolve) in Huntsville, Alabama, before being delivered to Northrop Grumman in Redondo Beach, California before being tested. Scientific InstrumentsThe Integrated Science Instrument Module (ISIM) is a framework that provides electrical power, computing resources, cooling capacity and structural stability to the Webb telescope. It is made with graphite-epoxy composite which is adhered to the bottom of the telescope structure of Webb. The ISIM has four scientific instruments and a guide camera. Near Infrared Camera (NIRCam) is an infrared imaging device that will have a spectral coverage ranging from visible edge (0.6 micrometer) to near infrared (5 micrometer). NIRCam will also serve as a wavefront sensor for the wavefront detection and control activities of the observer. NIRCam was founded by Chief Researcher Marcia J. Rieke and a team led by the University of Arizona. The industrial partner is Lockheed-Martin’s Advanced Technology Center in Palo Alto, California.The Near Infrared Spectrograph (NIRSpec) will also perform spectroscopy in the same wavelength range. The European Space Agency was built in ESTEC in Noordwijk, in the Netherlands. The head and the leading development team, Airbus Defense and Space, Ottobrunn and Friedrichshafen, Germany and the Goddard Space Flight Center; NIRSpec is a project scientist together with Pierre Ferruit (‰cole normale sup©rieure de Lyon). The NIRSpec design offers three observation modes: a low-resolution mode using a prism, a R ~ 1000 multi-object mode, and an R ~ 2700 integral field unit or long-slit spectroscopy mode. Modifying modes is done by operating a wavelength preselection mechanism called Filter Wheel Group and selecting a corresponding distributor element (prism or grid) using the Grid Wheel Assembly mechanism. Successfully both mechanics are based on ISOPHOT wheel mechanisms of the Infrared Space Observatory. Multi-object mode is based on a complex micro-shutter mechanism that allows simultaneous monitoring of hundreds of individual objects anywhere within the NIRSpec’s field of vision. Mechanisms and optical elements are designed, integrated and tested by Carl Carl Zeiss Optronics GmbH, Oberkochen, under the contract of Astrium. Under the Astrium contract. Under the Astrium contract. The Medium-Infrared Instrument (MIRI) will measure the medium to long infrared wavelength range from 5 to 27 micrometers. Contains both a mid-infrared camera and an imaging spectrometer. MIRI was developed as a collaboration between NASA and the consortium of European countries and is led by George Rieke (University of Arizona) and Gillian Wright (UK Astronomy Technology Center, Edinburgh, part of the Council for Science and Technology Plants (STFC)). MIRI has similar wheel mechanisms as the NIRSpec developed and constructed by Carl Zeiss Optronics GmbH under the contract of the Max Planck Astronomy Institute in Heidelberg. The completed MIRI Optical Countertop Group was delivered to Goddard for final integration into ISIM in mid-2012. The temperature of the MIRI must not exceed 6 Kelvin (K): a helium gas mechanical cooler placed on the warm side of the environmental shield ensures this cooling.Under the leadership of the Canadian Space Agency led by project scientist John Hutchings (National Research Council of Canada), the Thin Guideline Sensor and the Near Infrared Imager and Slit Spectrograph (FGS / NIRISS) are used to balance the line of sight at the observatory during science observations. Measurements made with FGS are used to control both the general orientation of the spacecraft and to drive the fine steering mirror for image stabilization. The Canadian Space Agency also provides the Near Infrared Imaging and Slit Spectrograph (NIRISS) module for astronomical imaging and spectroscopy in the 0.8 to 5 micrometer wavelength range managed by the lead researcher Ren© Doyon of the University of Montreal. Since NIRISS is physically mounted together with the FGS, it is often referred to as a single unit, but one is a scientific tool and the other serves completely different purposes as part of the infrastructure of the observatory.NIRCam and MIRI contain stellar lightstones to monitor weak targets such as off-planets and round star discs that are very close to bright stars. Infrared detectors for NIRCam, NIRSpec, FGS and NIRISS modules are provided by Teledyne Imaging Sensors (formerly Rockwell Scientific Company). The James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM) and Command and Data Processing (ICDH) engineering team use SpaceWire to send data between science devices and data processing equipment. Launch and Mission LengthAn Ariane 5 rocket is scheduled to be launched on March 30, 2021. The observatory is attached to the Ariane 5 rocket by means of a launching tool adapter ring, which can be used by a future spacecraft to tighten the observatory to address rough settlement problems. However, the telescope itself is not serviceable and the astronauts could not do things like swap tools, like the Hubble Telescope. The nominal duty period is five years with a target of ten years. The JWST must use propellant to protect the halo trajectory around L2, which provides an upper limit over its lifetime and is designed to carry it adequately for ten years. The planned five-year scientific committee begins after a 6-month operation. An L2 trajectory is only meta-stable, thus requiring orbital stations to be retained, or an object is dragged away from this trajectory configuration. Spacecraft BusSpacecraft Bus is the main support component of the James Webb Space Telescope, which houses a large number of computers, communications, drives and structural parts that bring together different parts of the telescope. Together with the sun visor, it forms the Spacecraft Element of the space telescope. JWST has two other component they are the Integrated Science Instrument Module (ISIM) and the Optical Telescope Element (OTE). ISIM’s 3rd Zone is also included in the Spacecraft Bus; the zone 3 having the ISIM Command, Data processing System subsystem and the MIRI cryo cooler. The Optical Telescope Element via the Openable Tower Group are related with The Spacecraft Bus, they are also connected to sunlight. While the structure of the Spacecraft Bus must support a 6.5-ton telescope, it weighs 350 kg (about 770 lb). Firstly, it is made of graphite composite material. Gathered in California by 2015 and was then required to integrate with the rest of the space telescope up to the planned launch of 2021. The bus can provide an arc second signal and isolate the vibration up to two milliseconds. The spacecraft bus is on the “hot” side facing the sun and operates at a temperature of about 300 K. Everything on the side facing the sun should be able to handle the thermal conditions of the JWST halo trajectory, one side under continuous sunlight and the other spacecraft in the shadow of sunlight. Another important aspect of the Spaceship Bus is its central computing, memory storage and communication equipment. The processor and software direct the data to devices, the solid state memory, and the radio system, which can send data back to Earth and receive commands.The computer also controls the signal and momentum of the spacecraft by receiving the sensor data from the gyroscopes and the star tracker and sending them to the reaction wheels or thrusters depending on the required commands.