Updated: Mar 2
Real size model of the James Webb Space Telescope. Image Credit: Wikimedia Creative Commons
The James Webb Space Telescope (JWST) has had a lot of attention from the public in the last few years. The JWST is a space telescope, traveling through space taking observations. Space telescopes either map the entire sky or select parts. The JWST was launched on December 25th, 2021 onboard the Ariane 5 rocket in Guiana, with the objective of learning more about the origins of the cosmos.
What is the James Webb Space Telescope?
JWST is a collaboration between the National Aeronautics and Space Administration (NASA) in the US, the European Space Agency (ESA), and the Canadian Space Agency (CSA). Some say that the telescope is an upgraded successor of the Hubble Space Telescope. Weighing about twice as much as its predecessor and harboring approximately 100 times the power, this will allow scientists to see deeper into space and therefore, further into the past. JWST should have the ability to gather information on stars and galaxies from 13.6 billion years ago, about 9 billion years before the Earth existed.
Mission objectives, and instruments
ESA advertises on their webpage that in order to fulfill the mission's primary objective that "it will observe the Universe's first galaxies, reveal the birth of stars and planets, and look for exoplanets with the potential for life." To do so, JWST is equipped with:
One near-IR camera
One multi-object near-IR spectrograph
A combined mid-IR camera and spectrograph
A combined observatory Fine Guidance System and near-infrared imager and slitless spectrograph
It is evident from the onboard instruments, that JWST will mostly look at the cosmos in the infrared - differing from Hubble which focused more on the optical and ultraviolet wavelengths.
As stars and planets are formed in clouds of dust and particles, these can obstruct our view and limit what we can see. Infrared light penetrates these clouds and allows us to see deeper into the universe. NASA estimates that JWST could reveal the formation of some of the oldest galaxies (approximately 100 million years after the Big Bang).
A comparison between the different visible and infrared wavelengths detected can be seen in the image below. As you can see, there's a lot more to be discovered!
Two images of the Eagles Nebula, otherwise known as "The pillars of creation", both taken by Hubble using different cameras. Image credit: NASA, ESA
Another advantage that the JWST presents is that its orbital position will be at the L2 Lagrange point, which is a staggering 1.5 million kilometers away from Earth and takes about 30 days to reach. This is quite the difference compared to Hubble's orbit of 547km above Earth. The Lagrange points are points of equilibrium in space around which a spacecraft can orbit (see image below).
This means that a spacecraft situated orbiting the L1 or L2 points can remain at a relatively constant distance from Earth and the Sun. Allowing for less light pollution induced by Earth and thus clearer observations!
Lagrange points between Earth and the Sun. Image credit: NASA
What are future satellites with similar missions? When will proper data be released?
At the moment of writing this blog, the JWST is already at the L2 point and is currently undergoing its mirror alignment and cool-down phase, before it can start calibrating its instruments. NASA has a dedicated webpage where anyone can track in real-time the telescope's orbital position in the solar system, instrument temperature, and which step has most recently been completed.
On February 11th, 2022 NASA released the first image taken by the telescope, of a star named HD 84406 located approximately 258 light-years away. As you can see in the image below the star is out of focus, which is normal, as the primary mirrors are not yet fully aligned.
James Webb Space Telescope's first image taken of HD 84406. The image contains 18 different snapshots of the same star; one for each mirror on the spacecraft. Image credit: NASA
Nonetheless, once the mirrors are aligned and the instruments are calibrated, the James Webb Space Telescope will begin to conduct its science routine. This usually occurs about 6 months after launch, and we are all excited to see what it finds!
The increase in diverse representation within the space industry is demonstrated through the staff of the JWST, such as Gregory L. Robinson who is one of the Webb Program Directors.
Gregory L. Robinson, Webb Program Director. Image credit: NASA
Being from Mauritius, myself, seeing the rise in examples of representation is encouraging. It warrants one to believe that space truly is for all and that people from any background or community can obtain one of the highest positions in the space sector.
This blog post was written by Chris Chellembrom.
Chris is currently undertaking his MSc at Politecnico di Milano in the field of Space Engineering. Having years of academic experience in the space sector, he hopes to transmit his knowledge and enthusiasm to the younger generation and adults unaffiliated with STEM.