NASA unveiled full-color images of the $11 billion James Webb Space Telescope (JWST) on Tuesday, marking the first of what will undoubtedly be many releases of the super-powerful optical instrument. But even taken in isolation, these five images mark a huge achievement and the culmination of a 26-year process to give humanity an even more detailed look at the early universe.
The image unveiled today followed the first image released Monday by President Joe Biden. That image, dubbed “Webb’s First Deep Field,” showed the cluster SMACS 0723, a massive vortex of galaxies that in reality represents just a slice of the universe the size of “a grain of sand on the tip of your finger at arm’s length,” as NASA says. administrator Bill Nelson put it on the live stream.
Today’s revelations include a galactic cluster and a black hole; the atmosphere of a distant planet; the epic death knell of a distant star; and a “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 were all known to astronomers. But thanks to the unprecedented sensitivity of JWST’s instruments and ability to view objects in the infrared spectrum, we can see these galactic shapes with greater clarity than ever before.
“Oh my god, it works,” Jane Rigby, scientist on Webb’s surgery project, said upon seeing the observatory’s first focused images. “And it works better than we thought.”
Signs of water and clouds on a swollen exoplanet
In the Milky Way alone, there are more than 5,000 confirmed exoplanets — or planets orbiting 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 Exoplanet program is to find signs of life in the universe; now, thanks to JWST, scientists can gather 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.
Which brings us to WASP-96 b, an exoplanet located about 1150 light-years away. It is a large gas giant more than twice as small in mass as Jupiter, but 1.2 times larger in diameter. In other words, it’s “swollen,” as NASA put it. It also has a short orbit around its star and is relatively unaffected by light emitted from nearby objects, making it a prime target for JWST’s optical power.
But this is not an image of an exoplanet’s atmosphere. It’s a picture of the transmission spectrum of an exoplanet, which at first glance may not be that exciting. However, this spectrum, captured by the telescope’s near-infrared image sensor and slitless spectrograph (NIRISS), showed unequivocal signs of water and even signs of clouds. Clouds! It’s an “indirect method” to study exoplanets, James Webb deputy project scientist Knicole Colón explained in a media briefing, but the telescope will also use direct observation methods in the coming year.
NIRISS can also capture evidence of other molecules, such as methane and carbon dioxide. Although these were not observed in WASP-96 b, they may be detectable in other exoplanets observed by JWST.
Shells of gas and dust emitted by dying stars
JWST has also looked at a planetary nebula officially called NGC 3132, or the “Southern Ring Nebula,” giving scientists more clues about the fate of stars at the end of their life cycles. NASA showed two side-by-side images of this nebula, one taken in near-infrared light (left) with the scope’s NIRCam and a second image taken with JWST’s mid-infrared instrument (right).
A planetary nebula is a region of cosmic dust and gas generated by dying stars. This particular one, located about 2,500 light-years away, was also captured by the Hubble Space Telescope, but NASA says this updated image from JWST provides more detail of the elegant structures that surround the binary star system.
Of the two stars (best seen in the right image), there is a fainter, dying star in the lower left and a brighter star that is in an earlier stage in its life. The images also show what NASA calls “shells” around the stars, each marking a period when the fainter, dying star (the white dwarf at the bottom left of the right image) lost some of its mass. It’s been expelling this material for thousands of years, and NASA said its three-dimensional shape is more like two bowls placed together at the bottom and opening away from each other.
The cosmic dance of Stephan’s Quintet
Stephan’s Quintet, first observed by French astronomer Édouard Stephan in 1877, shows the strange interaction of five galaxies with a level of detail never seen before. Consisting of nearly 1,000 individual images and 150 million pixels, this final image is JWST’s largest image to date, representing about one-fifth the moon’s diameter.
The image is somewhat misleading; the leftmost galaxy is actually far in the foreground, about 40 million light-years away, while the remaining four galaxies are about 290 million light-years away. These four galaxies are clustered so close together that they actually interact with each other.
The image even reveals a supermassive black hole, located at the center of the upper galaxy, which is about 24 million times the mass of the Sun.
I think this might be heaven
JWST also gives us a more in-depth look at the Carina Nebula, a region of the Milky Way about 7,600 light-years away. While we’ve been looking at Carina with Hubble, the new image shows hundreds of new stars, thanks to JWST’s ability to penetrate cosmic dust. The Carina Nebula reveals that star birth is not a peaceful, peaceful affair, but one characterized by highly unstable processes that can be as destructive as they are generative in some ways.
The amber landscape that flows across the bottom of the image marks the edge of the nebula’s massive, chaotic star-forming region — so massive that the highest points in this amber band, which NASA calls the “Cosmic Cliffs,” are about seven. light years high. Data from JWST will provide scientists with more information about the star formation process and can help them figure out why certain numbers of stars form in certain regions, as well as how stars end up with the mass they have.
Ultimately, these achievements are just the beginning. Scientists still have many questions — about exoplanets, the formation of the universe, and more — and now they have a new powerful tool in their arsenal to seek answers.