According to reports, the U.S. National Aeronautics and Space Administration's next-generation space telescope - the James Webb Space Telescope, has completed the primary mirror of the "gold coating" processing, which Space Telescope, is an important milestone. James Webb (JWST) space telescope will be the most powerful in human history, the space telescope, which will be launched into orbit in 2018. This week, NASA engineers completed the James Webb Space Telescope's 21 mirror surface (which faces the main mirror 18) coating covering the work, it is worth noting that gold coating mirror coating, which points to Weber Space Telescope is very important, because the space telescope needs to collect the faint cosmic far infrared light, the use of gold as a coating, increase of the universe's most distant collection of infrared light reflection.
According to James Webb Space Telescope senior project scientist John Mather Description: This week the telescope primary mirror coating means covering the end of a long mirror of the main structure is completed, the entire space telescope project also marks a major project node, is a milestone . The main mirror with a surprising new technologies, the main mirror is divided into 18 smaller hexagonal mirror, that is, the primary mirror using a new design concept, there are 18 mirror combination, the reason for using This design, because the James Webb Space Telescope if you use the traditional straight-type mirror structure, and to meet the design requirements of the observational accuracy, we need a larger rocket for launch, if the use of modular mirror layout, you can narrow telescope volume, but also to achieve better observation results. Hexagonal mirror almost every one has a high degree of it, is about 4.9 feet, or about 1.5 meters. Use materials made of beryllium, Zinc oxide beryllium manufacturing these mirrors to form a total area of ​​the mirror is the Hubble Space Telescope mirror the layout of the traditional six times, because of this innovative combination of the mirror, making the James Webb Space Telescope to accept the distant universe the ability to light the Hubble Space Telescope is more than 8 times, particularly for dark objects in the universe, the Hubble observation capacity is hundreds of times.
    And behind each mirror has a number of mini-micro-motor control, can produce no more than 10 nm displacement deviation, the reason for this design, the temperature is very low because of space, and space telescopes in the observation process, mirror needs to be directed towards a different direction, this time will produce small changes in temperature, which requires the mirror to the fine-tuning. Thus, mirror on the requirements in the choice of lighter materials, and greater strength, capacity should be required. Ultimately, 18 beryllium mirror system will be launched in space, forming a huge mirrors, height of 21.3 feet, about 6.5 meters. While the remaining three sides of the mirror space telescope will be used elsewhere.
    Starting from June 2010, NASA engineers began to mirror each piece of beryllium system for coating work, Titanium dioxide only to be coated with a thickness of 120 nm of 0.12 ounces of gold, and 120 nm is equivalent to a million feet one, than a fine human hair 200 times. The coating thickness of 120 nm, responsible for this work glossy coating contractors, directors IanStevenson that: in the James Webb Space Telescope primary mirror coating of gold, we are faced with many technical challenges, these coatings are not simple made, but the quantum paint, has a very complex production processes.
    More difficult task which is not the hardware back-up service must be run under the conditions, that is, the James Webb Space Telescope positioned at Lagrange points, the hardware must avoid the high failure rate. In order to "gold mirror" of the coating, the scientists heated the gold paint to 2,500 degrees Fahrenheit, about 1371 degrees Celsius, so that we can make the coating material from a solid into a liquid. Subsequently, the main mirror coating engineer to be evaporated to the beryllium-plated version of the system, and finally the coating coverage.
    As development costs continue to rise, and has repeatedly postponed the original plan, the James Webb Space Telescope project has been facing in the withdrawal of the dilemma, the primary mirror coated end of the work, Magnesia making the project successful scientists see the dawn. James Webb Space Telescope project is funded by the U.S. National Aeronautics and Space Administration and the European Space Agency and Canadian Space Agency, a joint venture co-operation plan, the reason is the former name of NASA's James Webb Secretary, he served as NASA Secretary, the Executive of the greatest "Apollo" moon-landing program.
    Now, the James Webb Space Telescope has been the total cost of $ 8.7 billion budget, is the result of the project budget overruns and project delays, the U.S. House Appropriations Committee recommended the cancellation of the task, Nickel oxide but the Senate subcommittee that will provide sufficient funds to continue the project. All in all, and fulfill the main gold-coated mirror work on the James Webb Space Telescope, is a major success. Maryland's Goddard Space Flight Center, NASA's James Webb telescope optics project leader Lee Feinberg said: The "gold paint" on the James Webb Space Telescope observations in terms of performance is critical, can be found to ensure that the telescope to see distant objects in the universe of potential. Source:www.mhcocm.com