The James Webb Space Telescope nears completion as NASA begins installing mirrors

By Kelly Hodgkins November 30, 2015

nasa webb telescope mirror james installed — NASA/Chris Gunn

NASA recently announced that it has installed the first telescope mirror on the next generation James Webb Space Telescope (JWST). This mirror is one of eighteen units that will be attached to the satellite, which scheduled to launch in late 2018. The James Webb Space Telescope is designed to replace the Hubble Space Telescope, which has been orbiting for 25 years and is reaching the end of its usable lifespan.

The hexagonal shaped mirror was installed on the JWST using a robotic arm inside a clean room at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Built by Colorado-based Ball Aerospace & Technologies, each mirror measured 4.2 feet wide and weighed 88 pounds. The mirrors are comprised of a lightweight beryllium material with a gold coating to reflect infrared light. All materials were selected specifically for their ability to operate at extreme temperatures as low as minus 406 degrees Fahrenheit. When all 18 mirrors are installed, the telescope will function as one large 21.3 foot (6.5 meter) mirror that will fold for launch and then unfold and adjust to shape after it is deployed.

The JWST will expand upon the observations of both the Hubble Telescope and Spritzer Space telescope. It is being heralded as “the premier astronomical observatory of the next decade.” Unlike the Hubble which measures visible or ultraviolet light, the JWST will focus instead on infrared and near-infrared light astronomy. It will provide detailed information on the first stars and galaxies that formed after the Big Bang and will give astronomers an opportunity to study planetary and stellar formation. Astronomers hope to use the data collected from the JWST to learn more about the development of our solar system as well as possibly discover other solar systems and exoplanets similar to the Earth that are capable of supporting life.

The James Webb Space Telescope is being developed as part of a collaborative international effort that is lead by NASA along with contributions from the European Space Agency (ESA) and the Canadian Space Agency.

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Kelly's been writing online for ten years, working at Gizmodo, TUAW, and BGR among others. Living near the White Mountains of…

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