James Webb Space Telescope Will Answer Some Of The Universe's Questions
Assembled for the first time just yesterday, the James Webb Space Telescope (JWST), named after James E. Webb, a replacement for the Hubble Space Telescope (HST), will be launched into space in 2021 as one of the most premier telescopes for astronomical observation. Its high capacity of light capture will allow astronomers to detect distant objects in deep space. When a galaxy is more distant from us, according to Hubble’s law, it moves faster away from us and appears to be much dimmer and redder.
The Hubble Space Telescope was launched on April 24, 1990, so the technological differences between the (JWST) and the Hubble will be astounding.
Since this telescope will be capable of collecting extreme faint light from infrared that comes far away in space, the image taken by this telescope will reflect long into the past. It could even collect light near the era of reionization, when the first stars and galaxies were formed and lit up the universe for the first time. From those images taken, on a broader scope, scientists can try to build a history of the evolution of this universe, how our stars and galaxies were formed. In addition, data from different wavelengths in the light spectrum taken by JWST can help reveal the physical and chemical properties of the early stars and galaxies.
One of the JWST missions was to detect the supermassive dark stars (SMDSs), as one possible candidate of the first generation stars and also the subject of my current research, that formed not long after the big bang and fueled by dark matter. The weight of these extremely heavy stars, up to a billion times as massive as our sun, and extremely luminous postulated by simulation, made it possible for JWST to detect those individual objects. Finding those SMDSs can help explain why supermassive black holes in the center of galaxies exist.
The assemblage and launching of JWST is a tough process. This project was first initiated in 1996, and the launch was planned in 2007. However, due to budget issues and a major redesign in 2005, the actual launch date was postponed again and again. Currently, the launch is scheduled in early 2021. In the designing of this telescope, many innovative technologies were applied. For example, to block the infrared light from the sun, the earth, and the moon, engineers in the team have designed an intricate five-layer sun-shield, which is critical to the success of its mission. Also, a cryocooler was applied for cooling the detector to 7 kelvin so that the infrared detector could function normally.
After the telescope’s assemblage, to ensure the success of its mission, JWST will go through several deployment and environmental test before its expected final launch.
Written by Saiyang Zhang, Edited by Ariel Silverstein & Alexander Fleiss