The James Webb Space Telescope is the most powerful space telescope, including Hubble. It was so large that it had to be folded like origami in order to fit on the rocket that carried it into space. Because it is so precise and sensitive, it must be kept at temperatures close to absolute zero to prevent its own internal heat radiation from interfering with its sensors. It cost $10 billion to produce and took decades to complete because it was so expensive and complicated. There were 300 potential failure points between it and functionality. But now it has arrived. And it has an incredible mission: to study planetary systems for signs of life; to understand the formation of planets, stars, and galaxies; and to peer across the universe at objects so distant that their light has traveled for nearly as long as the universe is believed to have existed. In other words, the JWST was designed to detect the first stars and galaxies at the edge of our observable universe, i.e., objects from the dawn of time.
And the first images have begun to arrive. I am Alex McColgan, and you are currently viewing Astrum. Join me on a journey as we examine the first photographs produced by the James Webb Space Telescope and witness the precision and power of this engineering marvel. It already shows promise of being spectacular. For those who are new to this channel, we have spent considerable time observing the JWST’s evolution from a work in progress to a fully realized piece of hardware. It was conceived in the 1990s with an initial budget of one billion dollars and a launch date of 2007. However, numerous obstacles and delays plagued the project, repeatedly delaying its completion. It finally launched in December 2021, having spent the preceding months slowly unpacking, powering up, and testing its hardware. It weighs 6,500 kilograms and has a sun shield measuring 14 by 21 meters, roughly the size of a tennis court. Its mirror for capturing light is six times larger in area than Hubble’s lens, allowing it to collect more photons from greater distances and produce more detailed images. It is equipped with numerous cameras and scientific instruments that enable it to view the entire infrared spectrum. This characteristic is essential to its specific mission.
Due to the expansion of the universe, all light from the farthest reaches of space has been stretched to the point where, regardless of what it was originally, it is now infrared light. Therefore, an infrared telescope is required to observe these light sources. In addition, infrared is more effective at penetrating dust clouds and other obscuring debris, giving the James Webb Telescope the incredible ability to observe objects that are beyond Hubble’s vision. This telescope is frequently compared to Hubble, as the James Webb Space Telescope was intended to be Hubble’s successor. However, due to their slightly different fields of view—Hubble can primarily see in visible light spectrums, whereas the James Webb Space Telescope can almost exclusively see in infrared and cannot see certain visible light spectrums at all—it is more accurate to say that the two telescopes complement rather than compete with one another. They form a formidable duo that expands our understanding of the universe. However, that is not why you are here. You are here to observe James Webb’s capabilities. Let’s begin in our own galaxy and gradually expand our vision to the edge of the observable universe. You will witness some breathtaking sights. Our first destination is a location known as the Cosmic Cliffs. The Cosmic Cliffs, also known as NGC 3324, are a portion of the Carina Nebula located approximately 7,600 light-years from Earth. These peaks are approximately 7 light-years tall and represent only a small portion of the entire nebula. The actual nebula is much larger and has a hollowed-out core where stellar winds have blown away all the nearby dust.
Here, we are observing the edge of this hollowed-out bubble. This region of space is of great interest to scientists for one very simple reason: it helps answer questions about the formation of stars. Due to stellar winds in this region, dust and matter congregate to form a region where stars are born. Despite our extensive stargazing, this process is still shrouded in mystery. How exactly do they form? What do the different stages look like? It is challenging to tell. Part of the difficulty in finding the answers is the dust itself, which is both essential to the process and a massive obstacle to its realization. It envelops the forming stars like a protective cocoon, preventing scientists from gaining a clear view of what is occurring at crucial moments. James Webb corrects this. Not only does this image provide more detail than Hubble’s image, but thanks to JWST’s onboard Miri, or Mid-Infrared Instrument, we can see what lies beneath the layers of dust. Note how much more distinct the image is! This will provide scientists with information about the formation of stars for an extended period of time. So much for star formation. At our next stop, the JWST uncovers more information about their demise. Let’s take a look at NGC 3132, also known as the Southern Ring Nebula, which is a little closer to home. The image on the left was captured by the Near Infrared Camera (NIRCam) of the JWST, while the image on the right was captured by MIRI once more. This is a planetary nebula, although that term is technically a bit of a misnomer. While regular nebulas are the birthplaces of stars, planets do not form in planetary nebulas. Instead, it was an unhelpful naming convention employed by early astronomers who observed the spherical shapes of these nebulas and assumed they resembled planets.
Even though our interpretation of the name has changed, the name has endured. This type of planetary nebula is created when dust and gas are expelled from dying stars at the end of their lives. Knowing the chemical composition of this dust is useful because understanding what materials exist in the universe enables us to predict the composition of future waves of stars. Therefore, once again, James Webb’s ability to remove layers of dust in order to see what lies beneath is invaluable. Compare this image to Hubble’s to get an idea of how much more detail JWST is able to capture. This has taught scientists that the second star in this system has not yet exploded, so the formation of its own planetary nebula is likely to occur in the future. We can also gain a better understanding of how the gravitational interactions of the two stars stir the nebula, creating fascinating patterns in the dust. Now let’s examine the universe beyond our galaxy. It makes sense to find a location like this if we wish to observe the formation of stars. A distance of 161,000 light years separates us from the Tarantula Nebula, so named because it conjures the image of a gigantic tarantula hiding in its silken web. In addition to its otherworldly beauty, this region is of particular interest to scientists due to its resemblance to the “Cosmic Noon” period in the history of the universe. To the best of our knowledge, this occurred approximately a billion years after the beginning of the universe, when star formation was at its peak. It is believed that conditions there would have resembled these. James Webb was able to detect stars as they were forming; this is a fascinating time period to study. Let’s refocus on the distant future.
As we expand our view, we lose track of individual stars and begin to perceive phenomena on a galactic scale. Even here, beautiful dances are being performed. Stephan’s quintet is a formation of five galaxies that was featured in the film “It’s a Wonderful Life” despite the fact that one of them is not actually adjacent to the others. It is believed that these four galaxies will eventually collide. In fact, two are already doing so. James Webb provides us with a clear view of the brilliantly hot dust ejected as the two central galaxies orbit each other. Here, the gravitational forces are mind-bogglingly powerful. The energy is intense. This dance is truly appreciable on such a grand scale. This image was not captured at a single moment, but rather is a compilation of nearly a thousand separate images taken by James Webb and then pieced together by scientists, giving it an incredible resolution for discerning minute details. The image known as Webb’s First Deep Field is so distant that even James Webb has to strain to see it. This image was captured from a region so small that a single grain of sand held at arm’s length would obscure its visibility in the night sky. At this scale, individual stars are nearly nonexistent; instead, galaxies predominate. Individual stars are too small to be detected at this scale. Here, (relatively) closer objects bend light around them, distorting what lies beyond. We can now see the outskirts of the universe. This image depicts one of the oldest galaxies ever observed. It is so distant that the light from its birth at the beginning of the universe has only recently reached us. Where is it located? We will need to zoom in closer. Do you see it? Admittedly, it is quite small. Scientists can determine how far this tiny red galaxy has redshifted and how long its light has been traveling by comparing it to the normal visible light emitted by similar sources. It was determined that this tiny dot was 13.1 billion light years away. Given the universe’s estimated age of 13.7 billion years, this is one of the earliest galaxies we will ever be able to observe. You may be disappointed by its diminutive size.
However, there is cause for optimism. Compare this image to a comparable Hubble image of the same region: Clearly, the image captured by JWST is more detailed and displays more objects. However, there is one additional significant distinction between these two images. Hubble captured this image by staring at this region of the sky for ten days, slowly accumulating every photon from this region of space into a single image. JWST, on the other hand, captured its own image in only half a day. Imagine how much more detailed an image JWST could capture if given a comparable amount of time, given that it was able to capture such a detailed image in 1/20th of the time. In other words, this tiny dot is likely not the best the JWST is capable of producing. I hope these images have given you a sense not only of the scientific advancements possible with the JWST but also of the breathtaking beauty of the universe. Images such as these astonish me.
Unfortunately, we will have to be patient to see what other discoveries the JWST has in store for us. The JWST has just completed its calibrations, allowing its instruments to cool and ensuring that everything is functioning perfectly. Over the next 5 to 10 years of its expected lifespan, there are lines of scientists vying for the right to utilize it. Each second is fiercely competed for. It will investigate exoplanets for signs of hospitable atmospheres for life, uncover nebula to discover the origins of stars, and help us understand the difference between an old galaxy like ours and the young galaxies that formed immediately after the Big Bang. Who knows what else we are about to discover with a tool as powerful as the James Webb Space Telescope?
