It’s not often that the sequel is as good as the original, but JWST’s second image release certainly lived up to expectations set by the jaw-dropping deep field released on Monday evening. In fact, it surpassed it by leaps and bounds.
The unveiling of that first image by President Joe Biden wasn’t exactly impressive, but the image itself? Magnificent. Known as “Webb’s First Deep Field,” it gives astronomers a look at the galaxy cluster “SMACS 0723.” The image itself is a minuscule patch of the Southern Hemisphere sky — equivalent to a grain of sand held up to the heavens — yet replete with thousands of galaxies, from spirals and ellipticals to simple pinpricks of light only a few pixels wide.
JWST’s First Deep Field was revealed on July 11.
And thanks to a phenomenon known as gravitational lensing, it provides us with the deepest — and oldest — view of the cosmos yet. That’s a lot to live up to, right?
Well, the suite of images released on Tuesday don’t reach quite so far back in space and time. But they are undoubtedly profound and equal to the First Deep Field in beauty and exquisite detail.
There are three major images in JWST’s first full-color set. Two focus on nebulas, huge clouds of dust and gas within which stars are born, and the other analyzes a region known as Stephan’s Quintet, a frightening corner of the cosmos where five galaxies are locked in an ultimately fatal dance.
Then, there’s the spectral data of WASP-96b — a really hot, gas giant exoplanet — which reveals the composition of its atmosphere in unprecedented detail. This one isn’t an image like you’d expect, but arguably something better. Spectral data helps us understand not what a space-borne object aesthetically looks like but rather what it’d be like to stand on it. And, as they say, the book is often better than the film.
Let’s break down each one and explain why JWST’s second batch of cosmic goodies is just as groundbreaking as its first.
The Nebulas
In short, nebulas are immense clouds of dust and gas that exist at either end of a star’s life. Some are home to fledgling baby stars being born while others are created by their explosive deaths. But in both cases, nebulas are responsible for some of the most stunning visuals of our cosmos — and through JWST’s lens, the most powerful infrared imager we’ve ever had, their marvel is only enhanced.
The dust and gas of a nebula would typically obscure our view of the features inside them — namely the stars that are just bursting to life. Our eyes, and even massive telescopes like the Hubble, can’t penetrate such curtains of gaseousness. JWST’s infrared imagers, however, can easily get past them to see what’s going on inside. They also offer a much better resolution than a telescope such as Hubble does, so JWST is capturing the internal nebula show as well as external structure with exquisite clarity.
For its first nebula science discoveries, JWST focused on two separate stardust clouds: The Carina Nebula, located about 8,500 light-years from Earth, and the Eight Burst Nebula, which is much closer at around 2,000 light-years away.
Starting off strong, behold, the Eight Burst Nebula. It’s also known as the Southern Ring Nebula.
“This is a planetary nebula,” NASA astronomer Carl Gordon said. “It’s caused by a dying star that spilled a large fraction of its mass over in successive waves,” said Karl Gordon. And in fact, these waves can be clearly seen in the image.
On the left, you’ll see a version of the nebular image taken by JWST’s Near-Infrared Camera, or Nircam. This is often considered the telescope’s holy grail imager because it leads the charge in finding pieces of the invisible universe. In this case, Nircam helps illustrate the layers of light that connect to make up this complex system. Like a mixed-media painting, it offers a good deal of texture to showcase the different facets of the Southern Ring.
On the right is a version of the image that’s specifically drawn by JWST’s Mid-Infrared Instrument, or MIRI. And thanks to MIRI, we can see something like an easter egg in this photo. Right in the center of the cosmic eye, there are clearly two stars present. Not just the dying one, which is the one that looks redder on the left. The brighter, second star had been theorized to exist in the past…but had never been seen before.
According to NASA it will probably eject its own planetary nebula in the future — but until then that star will continue to influence the nebula’s appearance, giving us the vivid spectacle we see today. “As the pair continues to orbit one another,” NASA says, “they ‘stir the pot’ of gas and dust, causing asymmetrical patterns.”
Also, on that right-hand image, if you glance towards the top left, you’ll see a mysterious blueish line that appears to have flung out from the nebula. This line has its own story.
“I made a bet that said ‘it’s part of the nebula,'” Gordon said. “I lost the bet, because then we looked more carefully at both Nircam and MIRI images, and it’s very clearly an edge-on galaxy.” Yep, there’s an entire faraway galaxy lurking in this picture.
Next up is the Carina Nebula — once again, courtesy of JWST’s Nircam and MIRI.
“Honestly, it took me a while to figure out what to call out in this image,” NASA astrophysicist Amber Straughn said. “There’s just so much going on here. It’s so beautiful.”
This astonishing image is technically the edge of a giant cavity within a nebula called NGC 3324, known as the Carina Nebula. Within, you can see an incredible wealth of emerging stellar nurseries and individual stars that call this nebula home. Until now, all those cosmic sparkles were completely obscured from our view due to the thick dust and gas surrounding them — but JWST infrared cameras literally pierced through that veil and accessed the valuable sights within.
Decoding this image could very well shed light on how stars are formed, what kind of star-making material goes into that stellar formation and even dissect the mechanism of violent, starry winds that affect the surrounding space.
Curious about all those hills, valleys and spikes? They are NASA scientists. As Straughn puts it, “we see examples of structures that honestly we don’t even know what they are.”
WASP-96b
The hot, gaseous, giant exoplanet, WASP-96b, is a scientific curiosity. Its parent star, WASP-96, lies about 1,120 light-years from Earth, making it the closest object in Webb’s first batch of images. Here it is.
OK, although this image isn’t what you’d normally think of when hoping for a sick space picture, it’s actually incredibly groundbreaking for the field of astronomy. Simply, what you’re looking at is direct spectral data of an exoplanet in a solar system beyond our own.
And while we don’t get a view of the planet hanging out in space by its star, this “spectra” clues us in to the ingredients that make up this foreign world. What astronomers detected is striking.
JWST’s spectral analysis of WASP-96b indicates a tell-tale signature of water vapor in the planet’s atmosphere as well as evidence of clouds and hazes, which are tiny solid particles that sort of act like pseudo-clouds in the atmosphere. But before you get too excited about packing up to move to WASP-96b, a world decked-out in H2O, note that this exoplanet is closer to its star than mercury is to its sun. That means all its water is not liquid. Oh, and, it orbits that star every three and a half Earth days.
This is probably (definitely) not habitable for us Earthlings.
Regardless, this is an intriguing finding because while astronomers have, so far, located over 5,000 worlds outside of our solar system – and studied them with Hubble – WASP-96b has always stood out for its potentially unusual atmosphere.
“Most close-in exoplanets that have been studied with Hubble have flat, white spectra, which is taken as evidence that they are very cloudy,” says Benjamin Pope, a planetary scientist at the University of Queensland in Australia. Clouds are a nuisance because they prevent astronomers from getting a good feel for the composition of an exoplanet’s atmosphere. That’s not a problem with WASP-96b.
“It has the clearest skies of any exoplanet we know of,” says Coel Hellier, an astrophysicist at Keele University who was a member of the team that discovered the planet.
In the grand scheme of things, this spectral data is proof of concept that JWST will be able to assess the composition of many planets’ atmospheres. “It’s nothing like our solar system planets,” Knicole Colon, an astrophysicist at NASA said. “But that’s okay – because what we’re seeing is, again, the first exoplanet data from Webb. And this is just the beginning.”
While astronomers have long used Hubble, and other telescopes, to gather data about exoplanets and their atmospheres, there’s just nothing like JWST. “JWST is just going to be so much better for this,” notes Pope.
WASP-96b is the first of many and it shows Webb works as we hoped. What comes next will likely change how we think of planets outside of our solar system.
Moving on — what can Webb teach us about galaxies? As it turns out, quite a bit. Say hello to your new galactic muses.
Stephan’s Quintet
Last but absolutely not least for NASA’s Tuesday JWST image release is the breathtaking glimpse we get of Stephan’s Quintet.
This dramatic grouping of galaxies was discovered in the 19th century, long before the first space telescopes — well, even the first satellites — made it to orbit. It’s a bright region of space, made up of five galaxies and home to a huge shockwave courtesy of two galaxies colliding at extreme speed. We’ve been observing it from Earth for almost 150 years and Hubble has also captured striking images of the grouping.
Of today’s image releases, the Quintet is the farthest from Earth, with the galaxies located between 39 and 340 million light-years from Earth (one of the galaxies, NGC 7320, is much closer than the other four).
In this gigantic image, JWST revealed the Quintet with so much detail that we can literally see individual stars speckling the galaxies. The one on the left, in particular, is a starry spectacle. But perhaps the most incredible aspect of this photo we’re looking for has to do with the top-most galaxy. It has an active galactic nucleus — aka, a supermassive black hole 24 million times the mass of the sun. This void is pulling in materials and spitting out light energy equivalent to the burning of 40 billion suns.
JWST’s Nirspec and MIRI teamed up to dissect the features of this black hole, offering proof of matter swirling around the abyss.
Further, if you zoom out and peruse the background of this image, you’ll see lots of other galaxies speckling space. And that’s just a happy accident that we might want to get used to. JWST is so powerful and precise that it’s nearly impossible for it to take an image of what we’d consider “blank space.” It can’t help but capture the cosmic treasures every time. It’s just…too good.
It’s also extremely efficient, which is why we can expect an unending influx of images and spectral data as incredible as JWST’s first full set.
“Hubble’s extreme deep field was two weeks of continuous work,” Bill Nelson, NASA administrator said. “Imaging with Webb, we took that image before breakfast. The amazing thing about Webb is the speed at which we can churn out discoveries”
Although encapsulated in pomp and announced to the sound of champagne glasses clinking, everything we’ve seen from JWST, in this broadcast, took something like a week to put together. “We’re going to be making discoveries like this every week,” Nelson said.