Eye in the Sky – The Next Generation Space Telescope

The James Webb Space Telescope (JWST) is a cutting-edge space observatory that is slated to launch in October 2018.  Designed to be the primary space observatory for the next decade, the JWST is considered to be the successor to the Hubble Space Telescope, with plans to both complement and expand upon contemporary discoveries.  Using innovative design and engineering, its goal is to implement a broad range of astronomical and cosmological investigations with hopes to revolutionize current comprehension of the universe.

Conceived in 1996 by members of NASA, the European Space Agency, and the Canadian Space Agency, astronomers and engineers were intoxicated by the idea of building a bigger telescope with increased range and abilities.  The next frontier of space exploration seemed to lie in the infrared spectrum.


James Webb Space Telescope artist
Artist’s impression of the James Webb Space Telescope. Credit: NASA


Why exactly is infrared capability important?  Newly formed stars and planets are cradled in cosmic dust that absorbs visible light.  Infrared light has the ability to penetrate through this dust cloud, thereby exposing what lies inside. Furthermore, visible light from objects in the farthest reaches of the universe is subject to being stretched by the expansion of the universe.  By the time this light reaches earth, it lies in the long-wavelength infrared range. While Hubble does have some infrared capacity, the JWST has 100 times the sensitivity of current technology and will be able to offer up unprecedented imaging of astronomical objects.

In order to build a telescope with the power to operate into the most distant corners of space, this new creation had to be engineered differently.  To start, the JWST would need a gigantic mirror to reflect all of the infrared light for which it was created.  The mirror that has been designed is 6.5 meters across and has a collecting area roughly five times as large as Hubble’s.  Due to its enormous size, the mirror cannot fit onto its launching rocket, the Ariane 5. Scientists had to segment the mirror into panels that will unfold once in space.

Another obstacle was heat generated by the sun.  For the JWST to operate best, it would require a temperature of about -233 degrees Celsius — a mere 40 degrees above absolute zero.  To make this possible, engineers have designed a multi-layered sunshield that will reduce solar heat to approximately one-millionth its normal value.  Perhaps the most terrifying aspect about the entire project for scientists is that once in orbit, the JWST will be 1.5 million kilometers from Earth.  Unlike Hubble, which suffered optical complications that were corrected by a space shuttle mission, this telescope will be too far from Earth for any attempts at repair should there be a problem.


James Webb Space Telescope Construction
Construction of the James Webb Space Telescope at NASA. Credit: Desiree Stover/ NASA


Mission goals for the JWST include measuring the physical and chemical properties of planetary systems, understanding the formation of stars and planets, and imaging star-forming clusters.  Perhaps the most important and absolutely mind-blowing outcome the JWST hopes to achieve is to uncover evidence of the first galaxies or luminous objects formed after the Big Bang.  In theory, it could be looking into the infancy of the universe and perhaps, just perhaps, detecting signs of life.

The James Webb Space Telescope is a revolutionary astronomical observatory that is being built with the hopes of supplementing current knowledge and then surpassing what is known about the universe.  Using state-of-the-art engineering, the JWST will be the first of its kind to detect infrared light at such a high resolution.  Twenty years in the making, it has been an undertaking of epic proportions, involving countless scientists and engineers.  When launched in 2018, the James Webb Space Telescope will carry with it not only the most ground-breaking technology, it will also carry the hopes of many for discovering the origins of the universe.

Reference: James Webb Space Telescope/ NASA