How the James Webb Space Telescope changed astronomy in its first year

As Christmas approached last year, astronomers and space fans from around the world gathered to watch the highly anticipated release of the James Webb Space Telescope. Thought of as a marvelous feat of engineering, the telescope was not without its controversies — from being way over budget and behind schedule to receiving the name of a former NASA administrator who has been accused of homophobia.

Despite debates over the telescope’s name and history, one thing has become abundantly clear this year: JWST’s scientific prowess is remarkable. Beginning its science operations in July 2022, it has already enabled astronomers to gain new views and uncover mysteries on a wide range of space topics.

JWST’s most pressing goal is one of the most ambitious projects in recent astronomy history: looking back at some of the very first galaxies, which formed when the universe was brand new.

Because it takes light to travel from its source to us here on Earth, by observing extremely distant galaxies, astronomers can actually look back in time to see the first galaxies that formed more than 13 billion years ago. years.

I thought there was some discussion among astronomers about the accuracy of some of the earliest detections of the earliest galaxies: JWST’s instrument had not been fully calibrated, so there was some leeway about the exact age of the most distant galaxies. Recent findings have supported the idea that JWST has detected galaxies of the first 350 million years after the big bang.

That makes these the first galaxies ever observed, and they had some surprises in store, like being much brighter than expected. That means we have more to learn about how galaxies formed in the early universe.

These early galaxies are identified through surveys and deep field imaging, which are used by Webb to observe large areas of the sky that may appear empty at first glance. These areas do not have bright objects like the planets of the solar system and are located far from the center of our galaxy, allowing astronomers to peer into the depths of space to detect these extremely distant objects.

JWST was able to detect carbon dioxide in the atmosphere of an exoplanet for the first time and recently discovered a lots of other compounds in the atmosphere of the planet WASP-39b as well, including water vapor and sulfur dioxide. That not only means that scientists can see the composition of the planet’s atmosphere, but they can also see how the atmosphere interacts with light from the planet’s host star, as sulfur dioxide is created by chemical reactions with light. .

Learning about exoplanet atmospheres is crucial if we ever want to find Earth-like planets and search for life. Previous generation tools can identify exoplanets and determine basic information like their mass or diameter and how far they orbit from their star. But to understand what it would be like to be on one of these planets, we need to know about their atmospheres. With the JWST data, astronomers will be able to search for habitable planets far beyond our solar system.

It’s not just distant planets that have caught JWST’s attention. Closer to home, JWST has been used to study planets in our solar system, including Neptune Y Jupiter, and will soon be used to study Uranus as well. By looking into the infrared range, JWST was able to pick out features like Jupiter’s auroras and a clear view of its Great Red Spot. And the telescope’s high precision meant it could see small objects even against the brightness of the planets, such as showing Jupiter’s rarely seen rings. It also took the clearest image of Neptune’s rings in more than 30 years.

Another important investigation that JWST conducted this year was that of Mars. Mars is the best-studied planet outside of Earth and has been host to numerous rovers, orbiters, and landers over the years. That means astronomers have a pretty good understanding of its atmospheric composition and are beginning to learn about its weather system. Mars is also particularly difficult for a sensitive space telescope like JWST to study because it is so bright and so close. But those factors made it the perfect testing ground to see what the new telescope was capable of.

JWST used both their cameras and their spectrographs to study Mars, showing the composition of its atmosphere, which almost perfectly matched the model expected from current data, showing just how accurate JWST’s instruments are for this type of research.

Another JWST goal is to learn about the life cycles of stars, which astronomers now roughly understand. They know that clouds of dust and gas form knots that accumulate more material and collapse to form protostars, for example, but exactly how that happens needs more research. They are also learning about the regions where stars form and why stars tend to form in clumps.

JWST is particularly useful for studying this topic, as its infrared instruments allow it to peer through dust clouds to see the inner regions where stars are forming. Recent images show the development of protostars and the clouds they spew and are facing regions of intense star formation, such as the famous Pillars of Creation in the Eagle Nebula. By imaging these structures in different wavelengthsJWST instruments can see different features of dust and star formation.

Speaking of the Pillars of Creation, one of JWST’s greatest legacies in the public mind is the stunning images of space it has captured. From the international excitement in the revelation of the first images from the telescope in July a new views of iconic views Like the Pillars, Webb’s images have been everywhere this year.

as well as the beautiful Carina Nebula Y first deep fieldother images worth taking a minute to admire include the sculpted shapes of stars from the Tarantula Nebulathe dusty “tree rings” of Wolf–Rayet binary star 140and the otherworldly glow of Jupiter in the infrared.

And the images keep coming: just last week a new image was released showing the glowing heart of the galaxy NGC 7469.

Here’s to a year of incredible discoveries, and many more to come.