I can’t believe we are finally nearing launch for James Webb Space Telescope. In 2004, when I had gone back to school, one of my physics professors tasked us with doing a presentation on a topic covered by his course, in lieu of a lab that week. I chose to do my presentation on current and forthcoming ground and space-based telescopes.
https://www.space.com/james-webb-space-telescope-final-mirror-test
A LONG time coming
At the time, James Webb Space Telescope was to have launched by the end of the decade: 2010. In 2011, an announcement was made to push JWST launch back to 2018. I couldn’t believe it!!! I have heard of schedule slips, but seven years??!!! Seven years!!!??? Since then, JWST has, obviously, been pushed back some more. It is now scheduled to launch on Halloween 2021. At the time I made the presentation in 2004, JWST had been being built for a few years already. Never in my worst nightmares did I imagine that it would take 20 years to launch this telescope.
Not a Hubble Replacement
Many people think James Webb Space Telescope is a replacement for the much loved and revered Hubble. It is not. Hubble observes primarily at visual wavelengths, whereas JWST primarily observes in the infrared. Hubble was last serviced in 2009 and, with the end of the Space Shuttle program, there is no hope of any more servicing missions. Hubble will eventually lose gyroscopes or some other major malfunction that will cause it to cease operation. JWST is not a replacement and is unlikely to be as loved or renowned as Hubble, but it is vital asset to the astronomy community, nonetheless.
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