The James Webb Space Telescope Is the Hubble Successor

By Dr. Gary L. Deel, Ph.D., J.D.
Faculty Director, School of Business, American Military University

I have written about the legacy of the Hubble Space Telescope and how it revolutionized our understanding of the cosmos. And Hubble still has more work to do, as it is not scheduled to be decommissioned any earlier than the mid-2020s. However, NASA is already looking to the next generation of space telescopes to continue our exploration of the universe. Center stage among these future missions is the James Webb Space Telescope (JWST).

The JWST is a 6,200 kg (136,686.6 pounds) infrared telescope with a 6.5 m (21.3 foot) primary mirror. The telescope is scheduled to be launched aboard an Ariane 5 rocket in 2021. Although the JWST is sometimes discussed as if it is the exclusive product of NASA, it is actually an international collaboration among the U.S., Canadian, and European space agencies.

The JWST’s Mission Is to Continue Exploring the Origin of Our Universe

The JWST’s mission is to continue exploring the origin of our universe, including galaxy and solar system formations. The telescope technically has four instruments, which include a near-infrared camera and spectrograph, calibrated for wavelengths between 0.6 and 5.0 microns; a mid-infrared instrument, which will cover between 5 and 28 micron wavelengths); and a fine guidance sensor so that the JWST can capture stable, high-quality images.

In comparison to Hubble, the JWST will be able to study the universe in longer wavelengths and with much greater sensitivity than Hubble ever could. Hubble’s instruments were designed primarily to capture data in the ultraviolet and visible light spectrums, while the JWST is focused on the longer wavelength infrared spectrum. This longer wavelength capture will allow the JWST to see further back in time through the depths of space, and with greater clarity.

The 6.5 M Diameter Mirror on the JWST Is Much Bigger than the Hubble’s 2.4 M Diameter

The 6.5 m diameter mirror on the JWST is much bigger than the Hubble’s 2.4 m diameter. Another distinction between these two telescopes is that, while Hubble orbits the Earth, the JWST will be positioned at the L2 Earth-Sun Lagrangian point. (Lagrange Points are positions in space where the gravitational forces of a two body system like the Sun and the Earth produce enhanced regions of attraction and repulsion.)  This choice in orbit was made to reduce light and heat interference caused by a planetary orbit, as the Earth reflects a lot of energy back into space that can distort the quality of images.

One final point of comparison between Hubble and the JWST is cost. When Hubble was launched, its initial cost was approximately $4.7 billion. After 20 years of operation it had cost another $5 billion or so, for a total of about $10 billion. By contrast, the JWST has cost about $10 billion just to design and construct it so far, and it hasn’t even launched yet. Here’s hoping the launch is successful when the time comes, as a failure would be an incalculable loss.

About the Author

Dr. Gary Deel is a Faculty Director with the School of Business at American Military University. He holds a J.D. in Law and a Ph.D. in Hospitality/Business Management. Gary teaches human resources and employment law classes for American Military University, the University of Central Florida, Colorado State University and others.