On Tuesday, NASA unveiled full-color images from the $11 billion James Webb Space Telescope (JWST), the first of many releases of the super-powerful optical instrument. But even taken on their own, these five images mark a huge achievement and the culmination of a 26-year process to give mankind an even closer look at the early universe.
The image unveiled today follows the initial release of the image by President Joe Biden on Monday. This shot is called “Webb’s First Deep Field”, revealed the SMACS 0723 cluster, a huge whirlpool of galaxies that is really just a piece of the universe the size of “a grain of sand on your fingertip at arm’s length,” as NASA administrator Bill Nelson put it on air. .
Today’s revelations include a galaxy cluster and a black hole; the atmosphere of a distant planet; the epic death knell of a distant star; and the “star nursery” where stars are born. We’ve seen some of these targets before, thanks to JWST’s predecessor, the Hubble Space Telescope, and they’ve all been known to astronomers. But thanks to the unprecedented sensitivity of the JWST instruments and its ability to see objects in the infrared spectrum, we can see these galactic shapes with greater clarity than ever before.
“Oh my God, it works,” said Jane Rigby, a Webb Operations Project Scientist, after seeing the first in-focus images from the observatory. “And it’s working better than we thought.”
Signs of water and clouds on a puffy exoplanet
There are more than 5,000 confirmed exoplanets in the Milky Way alone — or planets that orbit a star other than our Sun. The existence of exoplanets raises a fundamental question: are we alone in the universe? Indeed, the explicit goal of NASA’s Exoplanets program is to look for signs of life in the universe; now, thanks to JWST, scientists can get more information about these planetary bodies and hopefully learn more about whether life exists on these planets, and if so, under what conditions it can thrive.
This brings us to WASP-96 b, an exoplanet located about 1150 light years away. This is a large gas giant, which is more than half the mass of Jupiter, but 1.2 times its diameter. In other words, he’s “chubby,” as NASA put it. It also has a short orbital period around its star and is relatively uncontaminated by light emitted by nearby objects, making it a prime target for JWST’s optical power.
But this is not an image of an exoplanet’s atmosphere. This is an image of the exoplanet’s transmission spectrum that may seem less than spectacular at first glance. However, this spectrum, taken with the telescope’s thermal imager and slitless spectrograph (NIRISS), showed unambiguous signs of water and even signs of clouds. Clouds! It’s an “indirect method” for studying exoplanets, Knichol Colon, Deputy Scientist James Webb explained at a media briefing, but next year the telescope will also use direct observation methods.
NIRISS can also detect the presence of other molecules such as methane and carbon dioxide. Although they were not observed in WASP-96 b, they could be found on other exoplanets observed by JWST.
Shells of gas and dust emitted by dying stars
JWST also studied a planetary nebula officially named NGC 3132, or the “South Rim Nebula”, providing scientists with more information about the fate of stars at the end of their life cycle. NASA has shown two side-by-side images of this nebula, one taken in the near infrared (left) with the NIRCam telescope, and the second with the JWST mid-infrared instrument (right).
A planetary nebula is a region of cosmic dust and gas formed by dying stars. This particular image, about 2,500 light-years away, was also taken by the Hubble Space Telescope, but NASA says this updated image from JWST offers more details about the elegant structures surrounding the binary star system.
Of the two stars (best seen in the right image), there is a dimmer, dying star located in the lower left corner, and a brighter star that is in an earlier stage of its life. The images also show what NASA calls “shells” surrounding the stars, each marking a period when a dimmer, dying star (the white dwarf at the bottom left of the right image) lost some of its mass. It has been ejecting this material for thousands of years, and NASA has stated that its three-dimensional shape is more like two bowls placed together on the bottom and opening away from each other.
Cosmic dance of Stephen’s Quintet
Stephan’s Quintet, first discovered by French astronomer Édouard Stephan in 1877, shows the strange interaction of five galaxies in a level of detail never seen before. This final image consists of almost 1,000 individual images and 150 million pixels, and is the largest JWST image to date, representing about one-fifth of the Moon’s diameter.
The image is a bit misleading; the leftmost galaxy is actually far in the foreground, about 40 million light-years away, while the other four galaxy systems are about 290 million light-years away. These four galaxies are grouped so close to each other, relatively speaking, that they actually interact with each other.
The image even shows a supermassive black hole at the center of the uppermost galaxy, with a mass about 24 million times that of the Sun.
I think it might just be heaven
JWST also gives us a deeper look into the Carina Nebula, a region of the Milky Way about 7600 light-years away. As we looked at Carina with Hubble, the new image shows hundreds of new stars thanks to JWST’s ability to penetrate cosmic dust. The Carina Nebula shows that the birth of stars is not a peaceful and serene phenomenon, but a process characterized by highly unstable processes, which in some ways can be as destructive as they are creative.
The amber landscape at the bottom of the image marks the edge of a massive, chaotic star-forming region of the nebula – so massive that the highest points in this amber band, which NASA calls “Space Rocks”, are about 7 light-years high. The JWST data will give scientists more information about the process of star formation and could help understand why a certain number of stars form in certain regions and how stars eventually acquire the mass they have.
Ultimately, these achievements are just the beginning. Scientists still have a lot of questions — about exoplanets, the formation of the universe, and more — and now they have a powerful new tool in their arsenal to find answers.
Credit: techcrunch.com /