The Universe’s Eye: What has the James Webb Space Telescope seen?

Written By Yanlin Chen | USA

Did you know that there's a telescope people have been waiting for 25 years? A 25-year wait that changed astronomy forever. That telescope is the James Webb Space Telescope (JWST), built by NASA, the largest and most complex space telescope ever sent into space. It launched on December 25, 2021, and after a million-mile journey, it finally opened its golden eye on the universe. Unlike other telescopes (like Hubble), Webb telescope does not orbit around the Earth, it orbits around the Sun at the second Lagrange point (L2), about 1.5 million kilometers away from Earth. It was planned in the 1990s and construction officially began in 2004, with the support of thousands of skilled scientists, engineers and technicians from 14 countries across the world. 

Webb did not look like this before it was launched into space — Webb was folded up due to the limited space in the rocket, and when it arrives at the second Lagrange point, it has to unfold by itself. This means that, if the telescope does not unfold successfully in space, no one will be able to help it out, and the money ($10 billion) used to build the telescope will be money down the drain and the effort from all of the scientists will have gone to waste. Fortunately, the unfolding went perfectly. When it opened its golden eyes, no one in the control room was anything less than excited. Then, Webb took a picture of the deep universe. In the picture we can see that it included thousands of galaxies and each of them have included hundreds of millions of stars, and this fully embodies the beauty of the universe.

Before the Webb Space Telescope was built, the most powerful telescope humans had was the Hubble Space Telescope (HST). You might wonder what is the difference between Hubble and Webb, and why we built it. 

First of all, both of the telescopes are reflecting telescopes. But the difference is that Webb has a wider range of infrared vision (0.6 microns to 28.5 microns), which can see through the dust and the gas of massive clouds, and this allows Webb to see a lot more than Hubble. But this does not mean that we don’t need Hubble anymore. Hubble’s infrared vision (0.1 microns to 2.5 microns) can work together with Webb and cover a wide range in space. Webb is also about 2.5 times larger than Hubble, and this gives Webb more than six times the light collecting area that Hubble has.  

With the support of Webb, humans have found more detail about dark matter in the universe. It shows how the invisible, ghostly matter goes through and interacts with regular matter, which is the stuff that makes up stars, galaxies, and everything we see. It also shows how dark matter shapes the universe on a large scale; and keeps the galaxies together (like glue) as a cluster across millions of light years. Over time, scientists have found out that the spinning speed of galaxies is abnormally fast. This means there is not only matter we can see in the universe, there is also matter we cannot see; matter that has mass and affects how galaxies spin, and this matter is dark matter. 

“The JWST dark matter map is deeper and has higher spatial resolution compared to the initial map we made using Hubble Space Telescope data” (Bahram Mobasher). In other words, Webb gives us a longer sight and the ability to see places we weren't able to see before, also the ability to explore the unknown and beauty of the universe.

Webb can look all the way back to 13.5 billion years ago to see the first stars and galaxies forming out of the darkness of the early universe. Imagine looking at a picture that is actually 13.5 billion years old. This is the magic of light. If you travel 5 light years away from here, you will be able to see the Earth as it was five years ago. So, if you travel to about 4.54 billion light years from here, you can even see what the Earth looked like when it was first formed. 

In a sense, everything you see is in the “past” — you can never see what it looks like “now.” Even sunlight takes time to reach us. It arrives about eight minutes after leaving the Sun.  At the same time, this is also cruel; it means that interstellar travel is extremely difficult to achieve. Even the nearest star (Proxima Centauri) is about 4.2 light years away from us, which means it would take 4.2 years (at light speed) to arrive there. 

Of course, this isn’t entirely impossible either, a Warp Drive is a theoretically possible faster-than-light speed engine. However, given humanity’s current level of technology, achieving this remains extremely difficult and a distant prospect. Even though interstellar travel could be difficult, we still possess the courage to gaze up at the stars and to reach out and touch them. Once you think about it this way, what Webb does starts to make a lot more sense.

But the future of these discoveries is not guaranteed. After Donald Trump became president of the US, he cut off lots of the budget for science, and this also included space science. Due to the reduction of budget, NASA was forced to delay its plans for several major projects including, but not limited to Mars Sample Return, Lunar Gateway probes, crewed missions to the Moon and Mars. 

Luckily, in January 2026 Congress successfully secured a budget of $24.4 billion for NASA, and $208 million for the Webb telescope (Planetary Society). However, following the success from the budget increase, Trump again mentioned that the budget for 2027 would be decreased to $18.9 billion (AAU). So, even though Congress had stopped the budget from reducing, there are still a lot of unpredictable factors. While JWST continues to send back incredible images, the biggest challenges for space science in the coming years may not be technical; it may be political instead. The Atlantic described these actions as “An Act of Cosmic Sabotage.”

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Yanlin Chen | USA
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