The James Webb Space Telescope (JWST), finally launched on 24th December 2021 as a nice Christmas present for curious humans. It has had a long development path since it kicked off initially in 1989 and there was even some controversy over its name (well summarized in these Why This Universe and Dr Karl Kruszelnicki’s Shirtloads of Science podcasts)
It is bigger (around 6.5m {21ft} vs Hubbles 2.4m {7.8 ft}), more complex and riskier than the Hubble telescope in near Earth orbit. The JWST will be positioned about 1 million miles (vs Hubble's 340 miles) from Earth at L2 – the second of 5 Lagrange Points. Lagrange points are wonderful accidents of gravity and orbital where gravity from the sun and Earth balance the orbital motion of a satellite. Putting a spacecraft at any of these points allows it to stay in a fixed position relative to the Earth and sun using a minimal amount of energy for course correction, enabling longer missions).
The star image shown in the middle of the JWST shows a characteristic circular lens artifact. The JWST, with its main mirror made up of 18 hexagonal elements (each made from a honeycomb of gold-coated beryllium to reduce weight and improve infra-red light capture), will produce capture images having a distinctive native effect touched on by Mark McCaughrean (ESA's senior science advisor) in a November 2021 Space Boffins podcast (about 15min in).
JWST’s successful unfolding is covered in Nature here
LINKS TO DESIGNS
JWST Looks Back To Cosmic Dawn
PODCASTS
A good summary of the naming controversy and the JWST uses is on the Shalma Wegsman and Dan Hooper Why This Universe podcast
The Hubble and The James Webb telescopes compared
NASA’s site link to the JWT orbit is here
Shownotes
Lagrange Points
- Lagrange Points – Detailed explanation including mathematics and lots of links
- What are Lagrange Points? – ESA
- Lagrangian Points
Professor Mike Merrifield (Sixty Symbols) explains Lagrange points on Youtube
Some other podcasts covering the mission are below.
New Scientist podcast Nov 2021
Space Boffins, James Webb with Mark McCaughrean (ESA's senior science advisor), Nov 2021
NASA’s Curious Universe podcast series on James Webb telescope Nov/ Dec 2021
Building A Cosmic Time Machine an overview of the engineering
Internationalism and inspiration for women in STEM
YOUTUBE
How The JWT will transform Our Place In The Universe
Why you should believe the HYPE for the James Webb Space Telescope –Dr Becky Smethurst, University of Oxford astrophysicist
The Insane Engineering of JWT - Real Engineering
Hubble and James Webb Telescopes – The Story so Far - Curious Droid