Peering Into the Past

The National Aeronautics and Space Administration (NASA) is putting the finishing touches on a 25-year project to launch the largest telescope ever built early in 2021. Dubbed the James Webb Space Telescope (JWST), the $9.6 billion telescope is designed to orbit one million miles above the Earth and observe objects billions of lightyears away.

The main feature of JWST is the mirror, which measures more than 21 feet (6.5 meters) in diameter (seven times the size of the Hubble Telescope mirror). Constructed of strong yet lightweight beryllium and coated with a microscopic layer of 24 karat gold polished within nanometers of accuracy, it reflects 98 percent of infrared light onto a secondary mirror. From there, it is beamed to four instruments for analysis – one of which is a near-infrared spectrograph that can observe up to 100 objects simultaneously. Because infrared waves are created as the universe expands, analyzing these waves will allow scientists to see farther into the universe.

The mirror is made up of 18 different sections that will fold up to fit inside a 16-foot diameter Ariane rocket fairing. The 14,000-pound mirror will then unfurl once it reaches orbit – two to three weeks after its launch from Guiana Space Center next March. It will carry enough fuel to operate for up to 14 years, however, scientists are already working on a robotic fueling mission to extend the life of the project.