Eps 8: Principles and functions of the James Webb Space Telescope
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Valerie Steward
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Its remote location will allow Webb to observe the universe farther than the Hubble Space Telescope. According to NASA’s JWST website, following in the footsteps of ESA’s Herschel Infrared Observatory, the Webb telescope will be located at the so-called L2 point 1.5 million kilometers from the earth. This will give it a clearer picture of the universe than the Hubble telescope in low-Earth orbit, but it has a drawback.
Unlike Hubble, who was rescued during a space shuttle flight that fixed his faulty optics, he is too far from Earth to be repaired. The world's largest and most sophisticated space observatory will now be delivered to its launch pad, the European Kourou Cosmodrome, where operational preparations will begin two months before launch. The spacecraft will then separate from the rocket and travel for about a month before finally arriving at its destination, according to NASA's JWST website.
After the telescope is completed, Webb will initiate the next major part of its integration and testing program. NASA's Goddard Space Flight Center is leading the development, and the Space Telescope Science Institute will manage Webb after launch. Webb is an international program led by NASA with its partners, the European Space Agency and the Canadian Space Agency.
To encourage participation in Webb events throughout Arizona, and in collaboration with four SciAct ASU projects, including the SCoPE School of Earth and Space Exploration and the Infiniscope ASU projects, the school has created a Webb calendar of events with 15 select NASA organizers across the state. ... In honor of this historic launch and to highlight ASU's involvement in this mission, the university is joining nearly 500 event organizers across the country that have been selected by NASA to host a series of Webb-inspired events that bring together the scientists behind the telescope. This virtual event will be attended by experts in the field of earth and space sciences, with a special focus on the Webb Telescope.
This conference will include a panel discussion with Webb's Q&A session with American University scientists and students working on the telescope mission, including Windhorst. During this event, they will share the research they and their staff are doing on Webb. The data will be transmitted from JWST to Earth via NASA's deep space network, processed and calibrated at STScI, and then disseminated online to astronomers around the world.
Thanks in part to Webbs' size and infrared vision, here are five things a telescope will allow astronomers to do. First, it is large, with a main mirror 21.3 feet high, making Webb the farthest telescope that humankind has ever built. Second, Webb sees the Universe in infrared light, in the electromagnetic spectrum with slightly longer wavelengths than visible light.
It will be the only dedicated infrared telescope in space that can see long distances. The closest enemy, Hubble, operates primarily in the visible range and has a limited infrared range of sight. This is one reason infrared telescopes like Webb are so important.
Objects in the distance are also very small, so the telescope must be able to focus the light as close as possible. The far-infrared telescope of the Space Observatory. Herschel has a primary mirror with a diameter of about 3.5 meters and can only see something about 100 times thicker than JWST. Spitzer's retired infrared telescope was much smaller than Weber, and could not see so far into space.
Webb, the farthest telescope ever in existence, could destroy the youngest-looking galaxies that humanity can observe. The more scientists can look into space, the further in time they can observe the galaxy.
Webbs' infrared eyes on the universe will allow us to see the space where we were previously blind. The James Webb Space Telescope will detect infrared light 400 times weaker than what modern space telescopes can see. If this sounds familiar, it's because Webers mirrors do the same thing, but instead of reflecting infrared light into space, they direct it to the telescope's scientific instruments as accurately as possible.
Inside, these instruments are bolted to a structure that fixes them in space, filled with infrared light—focusing and diffusing, laser needles, and uniform beams—to test their response. At first glance, the result looks more like a radio telescope than an optical telescope.
Previous infrared space telescopes, such as the Spitzer Space Telescope, also worked in this way, but Spitzer is very small compared to Weber — Spitzer’s diameter is only 34 inches compared to Weber’s 21 feet. Weber is the largest space observatory ever, but to pack such a large telescope into a rocket, engineers must design it to fold into a smaller structure. The Hubble telescope is composed of a single piece of glass, but the Webbs folding mirror must be segmented and composed of individual hexagonal fragments. This design is used in many ground-based instruments, including the Keck telescope in Hawaii.
One technique combines very thin glass front plates with composite cores to form multilayer mirrors. Another method connects bezels to composite backplane structures using actuators. In the latter case, actuators can be used to actively control the mirrors in order to correct distortions.
The mirror consists of 18 individually adjustable gold-plated beryllium hexagonal parts. In space, Weber will open, his instruments will be carefully checked and calibrated, and his mirrors will be adjusted to optical perfection. This particular point in space will allow Weber to easily orbit the sun with the earth, allowing the telescope to transmit large amounts of data to the earth.
The telescopes' coldness and distance from Earth will allow JWST to accurately observe the red-shifted light of the early universe. The JWST will far surpass both of these telescopes, as it will be able to see many more stars and much older galaxies.
MIRI has been added to the Webb to enhance the infrared capabilities of telescopes and to conduct many further studies. Webb's other half of the telescope and scientific instruments completed its own vibration and acoustic tests at Goddard and cryogenic temperature vacuum tests at NASA's Johnson Space Center in Houston before being delivered to Northrop Grumman last year.
Tests showed that the combined setup, which includes the Webb telescope and four of its scientific instruments, performed flawlessly at temperatures around -233 ° C, similar to those they would experience in space. In this test, the deployable turret was ordered to extend 48 inches over a period of several hours so that the observatory could complete this process after the spacewalk (Producer, Videographer, Editor - Michael McClair .