James Webb Space Telescope

For the rough 300,000 years that humans have existed on earth, our universe has always remained somewhat of a mystery. Stars have evolved from being ancient gods, and deceased Pharaoh’s, and portals to the heavens, to the large chemical bodies that we know they are today. Now, with the new James Webb Space Telescope (JWST) that was launched on December 25th 2021, our understanding of the universe is about to be greater than ever before.

The James Webb Space Telescope is more powerful than anything that has ever been sent into space before, and after 30 years in the making, 1 million miles travelled from earth, 50 successful deployment missions and 10 billion USD spent, it has finally delivered its first full-colour images and spectroscopic data.

The initial images were released to the public via television broadcast on July 12th 2022, and revealed not only the oldest and furthest galaxies ever seen by the human eye, but evidence of water on a planet 1,000 light years away, and incredible details about the birth and death of stars.

JWST operates using infrared technology which means it has the capability to study atmospheres, light frequencies and dark spots that have always been invisible to its predecessor, the Hubble Space Telescope. JWST is also positioned much deeper in space, at 1 million miles away from Earth compared to Hubble’s 340 miles. This allows us to see 13.5 billion years into the past, only 200-300 million years after the big bang.

“We are going to be able to find some of the earliest galaxies that have formed in the universe. The Hubble deep field only looked at one part of the sky and stared there for a long time. That was really our first look into the distant universe. James Webb is a big step beyond that, so not only will we be able to look at objects that are much further away from us and much deeper into the universe’s history, but we are going to cover a much larger area of the sky. We will be able to observe many thousands more galaxies than we could before with the Hubble deep field,”

says Dr Jeyhan Kartaltepe, Associate Professor from the School of Physics and Astronomy at the Rochester Institute of Technology.

“With Hubble, you don’t see very many of these early universe time periods, and what you can see is a bit of a smudge, or a blob. With JWST, we are able to resolve structure and learn a lot about the properties of our very early universe, and how the earliest structures are starting to grow. JWST will also tell us a lot about how these galaxies evolved from the very early universe until today, and will put together a timeline because we can see galaxies across a wide range of distances.”

The James Webb telescope has been in planning since as early as the 80’s, even before the Hubble Space telescope was launched. Its undertaking was so complex and intricate, with numerous science goals and technical challenges, that it required the collaboration of NASA, the Canadian Space Agency and the European Space Agency.

Building a telescope that has enough power and sophistication to enable such a vast array of projects is not a straight forward task. Engineers had to come up with a completely original design in comparison to Hubble. The JWST stands at about 4 storeys tall, has a giant mirror measuring 6.5 meters across and 22 feet high, and it has a sunshield the size of a tennis court. Because this telescope was too big to fit inside a rocket ship, engineers had to fold it up and then allow it to unfold once it was in space. As space bound rocket ships fail from time to time, over three decades worth of work and 10 billion USD were placed on the line. Furthermore, because the JWST telescope is positioned so far from Earth, if something went wrong with its deployments, there wouldn’t be repair missions like there was with Hubble.

“Honestly, the launch was definitely not the hardest part of this mission. Following the launch, we had two weeks of very intense, complex, complicated deployments to get this telescope unfolded. Everyone was really on the edge of their seats waiting for these deployments to happen,” says Dr Amber Straughn, Astrophysicist for the James Webb Space Telescope.

“The deployment of the sunshield was particularly intense. The sunshield itself was five layers and it had to unfold and then deploy the five layers, and there were hundreds of release mechanisms on the sunshield that all had to release at just the right time in just the right way. There were quite a few single point failures, so if one release mechanism didn’t work there would be nothing we could do to fix it. So this particular part of the deployment, watching the sunshield deploy, was incredibly stressful. But everything went off so well. The engineers had built an amazing, incredible telescope and after that two weeks I think all of us took a deep breath and there was definitely a big celebration after the last part of the deployments happened.”

The launch was so efficient, using less fuel than anticipated, and this extended the mission from 5 years to an estimated 10-15 years.

But it is not all about stars and galaxies. JWST was also built with a relatively new, exciting field in mind. Exoplanets, and in particular exoplanets that sit just outside of our solar system.

“We will be looking about 40 years back in time, which is literally in our backyard. The Trappist-1 system is what we can call the rock star of the exoplanet. This is a star that is very small, not much bigger than Jupiter, and has not one but seven planets transiting it. We know that these planets are of a mass and size similar to the earth, and three of them maybe four are in right in the habitable zone. This system is very close to earth, only 40 light years away, and this is the one that we will be looking at very hard, to find out whether these planets have atmospheres. If there is a system to point to where there is maybe life, this is the one, the Trappist-1 system,” says Professor René Doyon, Director of the Institute for Research on Exoplanets at the University of Montreal.

Big telescopes like Hubble and JWST only come along once every couple of decades, but according to Dr Amber Straughn, “the next big telescope is just around the corner.”

“The next big telescope like this that we are building is called the Nancy Grace Roman Space Telescope. So this telescope is not as big or expensive as JWST, but it is also an infrared telescope that is designed to see the universe in more of a broad sort of spot. So telescopes like Hubble and JWST are designed to see small parts of the universe very deeply, but by looking a little less deep and a little more wide, we can learn different things about the universe.”

Apart from JWST, many ground based telescopes will be coming online in the next few years complementing the size of the James Webb telescope.

On the topic of James Webb’s first images, Professor René Doyon says “nobody could predict this. We don’t know what’s next, and that’s the most exciting part.”