Breaking Down NASA Webb Space Telescope's First Images of the Invisible Universe
The JWST delves into nebulas, colliding galaxies and an active black hole, and even provides a breakthrough look at an alien world.
It's not often that the sequel is as good as the original, but the second image release from the James Webb Space Telescope certainly lived up to expectations set by the jaw-dropping deep field reveal that took place 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 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.
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 images released 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 delicately woven with exquisite detail.
There are three major images in the 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 even more valuable. Spectral data helps us understand not what a spaceborne 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 the JWST's second batch of cosmic goodies is just as groundbreaking as its first peek.
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, 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 the JWST's lens, the most powerful infrared imager we've ever had, their marvel is only enhanced.
You can read exactly how the JWST's infrared imaging works here, but the basic principle is it can access light -- emanating across the cosmos from stars, galaxies and other luminescent objects -- that's stuck in a region of the electromagnetic spectrum invisible to our eyes. And more specifically to nebulas, that "hidden" light, so to speak, happens to be the main kind shooting through their dust clouds.
That means our pupils, and even massive telescopes like the Hubble Space Telescope, can't penetrate nebular curtains of gaseousness. They're veils that typically obscure our view of the flashy features inside them -- namely, stars just bursting to life or those in the process of dying. The JWST's instruments, however, easily get past them via infrared imaging to check out what's going on inside. Plus, they offer a much better resolution than a telescope such as Hubble -- in effect, catching the internal nebula show as well as external structure with a sophisticated clarity.
Now that we know what we're about to look at, let's get into it.
For its first nebula science discoveries, the 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.
2022-07-13 03:30:35
