James Webb Space Telescope

The new era of space. Getting started.

Published in

Shyam Cortex

4 min readJul 18, 2022

The James Webb Space Telescope represents a giant leap forward in our quest to understand the universe and our origins. How did the universe begin? Are we alone in the cosmos?

Webb will help us answer scientific questions about the early universe, the formation and evolution of galaxies, the birth of stars and the properties of planets within and outside our solar system

How powerful is the James Webb telescope?
James Webb can detect the heat of a bumblebee as far as the moon — John Mather

History

Construction on Webb began in 2004.
By 2011, all 18 mirror segments were finished and proven through testing to meet required specifications.
Between 2012 and 2013, Webb’s individual pieces, constructed in a variety of locations, began to arrive at NASA’s Goddard Space Flight Center
In 2013, construction of the sunshield layers began.
From 2013 to 2016, Webb’s science instruments were packaged together and subjected to numerous tests of extreme temperature and vibration
From late 2015 to early 2016, the telescope optics and structures were assembled, featuring installation of all 18 of Webb’s individual mirrors on the telescope’s backplane structure to assemble the 21-foot mirror
In 2017, the telescope assembly and the package of science instruments were integrated into one unit and subjected to mechanical integrity vibration
Final environmental, electrical, functional, and communications testing continued until Webb was folded and stowed for the final time in 2021

What does it have onboard?

Quick Facts

Primary mirror size: 21.3 feet (6.5 meters) across
Mirror shape: The mirror is comprised of 18 gold-plated hexagonal deployable segments
Sunshield: Webb’s five-layer deployable sunshield is the size of a tennis court
Instruments: Webb has four science instruments: Near-Infrared Camera (nircam), Near-Infrared Spectrograph (nirspec), Mid-Infrared Instrument (MIRI), and Near-Infrared Imager and Slitless Spectrograph (NIRISS) with the Fine Guidance Sensor (FGS)
Wavelengths: Visible, Near Infrared, Mid Infrared (0.6–28.5 micrometers)
Travel distance: 1 million miles (1.5 million kilometers) from Earth
Location in space: Orbiting the Sun around the second Lagrange point (L2)

How different is it from other space telescopes?

Webb will study infrared light from celestial objects with much greater clarity and sensitivity than ever before. Unlike the short, tight wavelengths of visible light, longer wavelengths of infrared light slip past dust more easily. Therefore, the universe of star and planet formation “hidden” behind clouds of dust comes into clear view for Webb’s infrared instruments

The 18 gold plated primary mirrors reflect the light source to the secondary mirror and then it reachs the ISIM.

How is it sent to space?

The James Webb Space Telescope is too big to fit into any rocket payload fairing, so in order to get into space, it has to be folded up and launched in this more compact configuration.After launch it’s designed to unfold like origami which is an engineering marvel!

How good is it??

**This is result of just 12.5 hours of exposure time. Imagine what more can come up in the future.**

“If you held a grain of sand up to the sky at arm’s length, that tiny speck is the size of Webb’s view in this image. Imagine — galaxies galore within a grain, including light from galaxies that traveled billions of years to us!” — NasaWebb