摘要
詹姆斯·韦布空间望远镜(简称韦布望远镜)于2021年12月25日顺利升空.这台6.5 m口径望远镜是人类有史以来建造的最强大、最复杂的天文设备.尽管曾面临前所未有的技术挑战并导致发射日期一再推迟,但它目前已成功部署到遥远的日-地-拉格朗日-2轨道上,预计使用寿命可达10年以上.韦布望远镜的红外观测灵敏度大约是哈勃空间望远镜的100倍,其卓越的成像和光谱能力将为天文学多个领域带来重要突破.例如,它将首次探测来自宇宙大爆炸后年轻恒星和星系的第一束光,研究星系在宇宙学时标上的形成和演化,观测形成中的恒星-行星系统,寻找太阳系外行星存在生命的证据,等等.本文回顾了韦布望远镜的历史、发展和特点,介绍了有关的科学计划和前期科学观测项目,并展望了与其他望远镜联合观测的前景.
James Webb Space Telescope(JWST)was launched on December 25,2021.This 6.5-m space telescope is the most powerful and sophisticated astronomical instrument ever produced.Its concept study started in the 1980 s as the Next Generation Space Telescope,before the launch of the Hubble Space Telescope(HST).To achieve its ambitious science goals,its unconventional design employs many cutting-edge technologies.A large multi-layer sunshield blocks emission of the Sun,Earth and Moon,and keeps the telescope at a cryogenic temperature(~40 K).The primary mirror consists of 18 hexagonal segments made of gold-coated beryllium.Every mirror segment is supported by actuators for fine adjustments,to ensure the finest image quality.Major mirror components and the sunshield were folded into the launch vehicle,to be deployed in space.Despite unprecedented technical and budgetary challenges,JWST has been successfully deployed on to a remote Lagrange-2 orbit,which offers a stable thermal environment and other operational advantages.The latest estimate anticipates a lifetime considerably longer than 10 years.JWST is equipped with one mid-infrared and three near-infrared instruments,offering superior imaging and spectroscopic capabilities with ample redundancy.It is approximately one hundred times more sensitive than HST and one thousand times more powerful than ground-based telescopes and previous space infrared telescopes,enabling a broad range of breakthroughs in astronomy.JWST will play a key role in detecting“the first light”after the Big Bang because the prominent features of such light are redshifted(z~20)into the infrared bands and because infrared light can penetrate through dust around young objects.In addition,it will study the galaxy formation and evolution across the cosmic time,observe the birth of stars and planetary systems,find evidence of life beyond the Solar system,etc.The first batch of science data will be released shortly after six months of instrument calibrations.For the first year of JWST operation,286 science
作者
郑玮
江林华
Wei Zheng;Linhua Jiang(Department of Physics and Astronomy,Johns Hopkins University,Baltimore,MD 21218,USA;Kavli Institute for Astronomy and Astrophysics,Peking University,Beijing 100871,China;Department of Astronomy,School of Physics,Peking University,Beijing 100871,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2022年第9期834-841,共8页
Chinese Science Bulletin
基金
国家自然科学基金(11721303,11890693)资助。
关键词
航天器
天文仪器
宇宙学
星系
红外波段
space vehicles
astronomical instruments
cosmology
galaxies
infrared band
