제임스 웹 우주 망원경(JWST) will specialise exclusively in infrared astronomy to study early 우주. It will search for optical/infrared signals from the early 별 and galaxies formed in the 우주 soon after the Big Bang for a better understanding of the formation and evolution of galaxies and the formation of 별 과 행성의 시스템. JWST will also study 행성의 systems and the origins of life. The much-awaited JWST is now scheduled to be launched on 18 December 2021.
Usually, one focusses a telescope at a target to observe. But at times you deliberately focus on nothing and that change the course of a field of study. Decision to focus 허블 공간 telescope on nothing in the hitherto unexplored fields in the sky was one such incident that changed the course of astronomy.
의 많은 획기적인 업적 중 허블 스페이스 버튼 Telescope (HST), the deep field images taken over the course of 10 days in 1995 when it captured about 3000 images of galaxies at different stages of stellar evolution has revolutionised astronomy and changed our understanding of the 우주.
These deep field images were formed by the light that had travelled from the remotest locations of the 우주 for billions of light years through the expanding 우주 and had reached Earth now to be captured by the 허블 telescope after originally emanating from the early 별 and galaxies formed soon after Big Bang about 13 billion years ago. So, as such deep field images denoted early 별 and galaxies as they were then billions of years ago. This was truly remarkable feat.
But, this technique of capturing primordial optical signals for developing understanding of early 우주 could not be an effective methodological tool due to the fact discovered in 1929 by Edwin 허블 그 우주 is expanding and all galaxies are moving away from each other as evidenced by the redshift of 은하’s spectrum to higher wavelengths in infrared (IR) region. But the 허블 telescope is equipped to observe in UV, visible and near-infrared region hence the need for an exclusive infrared 전망대 in 공간.
XNUMXD덴탈의 제임스 웹 우주 망원경(JWST) is thus a successor to the 허블 공간 telescope (HST) in the sense that the 제임스 웹 telescope aims to carry forward the 허블 telescope’s legacy in the area of study of early 우주. JWST will operate exclusively in infrared astronomy and has following four key goals:
이러한 이유들로, JWST needed to be different from 허블 telescope in design and operation. It is a reflecting telescope designed to capture near-infrared radiations from ultra-deep fields with a large origami-style mirror that makes it 100 times more powerful than 허블. 사실상, JWST 가장 큰 공간 telescope ever. To maintain its unprecedented infrared sensitivity, JWST has protection from infrared contamination from sun through a highly effective 5-layer sunshield. Further, to help maintain its very low operating temperature of 50 Kelvin (-223° C or -370° F), JWST will be placed in an 궤도 around the sun in the cold shadow of Earth all the time near the second Lagrange point (L2) of the Earth-Sun system at a distance of about 1.5 million km from Earth.
배치 JWST near far off Sun-Earth system L2 궤도 means, unlike 허블 telescope which received several repairs and maintenance in the 공간, JWST will be completely on its own after launch therefore there is no scope of any error at all. Perhaps this explains why launch of JWST is almost eternally delayed.
지금, JWST is planned to be launched on 18 December 2021.
As on 02 November 2021, JWST has already safely arrived at its launch site in French Guiana and the technical team is preparing for lift off on 18 December.
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출처 :
- NASA 2021. Webb telescope – The Road to Launch and Beyond for NASA’s James Webb 스페이스 버튼 Telescope. Posted 02 November 2021. Available online at https://www.nasa.gov/feature/goddard/2021/the-road-to-launch-and-beyond-for-nasa-s-james-webb-space-telescope
- 나사. JWST – Webb에 대한 일반적인 질문. 온라인에서 사용 가능 https://www.jwst.nasa.gov/content/about/faqs/faq.html
- 나사. JWST – 주요 사실. 온라인에서 사용 가능 https://jwst.nasa.gov/content/features/keyFactsInternational/
- ESA. 과학 및 탐험. Webb – 더 멀리 봅니다. 온라인에서 사용 가능 https://www.esa.int/Science_Exploration/Space_Science/Webb
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