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In a recent NASA announcement, the James Webb Space Telescope (JWST) Science Team released five spectacular images in their first science package.
Smarter, more educated astronomers, researchers, and scientists than I have spent a lot of time giving their thoughts on what we can see in each of these images.
But let’s take a moment to look at what NASA has released and understand why NASA chose this set of images for the first science release.
One of the unique features that will adorn nearly every image taken from the JWST will be the iconic “diffraction peaks” that appear around stars in an image. As shown in Image 1 above, nearby stars in the field of view will have a pattern of eight-pointed stars emanating from the center of the star.
These spikes seen in the image are not real, but rather come from light being diffracted as it bends around the secondary mirror supports on the JWST structure and the edges of the hexagonal mirror segments.
Any object with a diffraction peak seen in a JWST image will be a star that is in our “galactic neighborhood”, i.e. a star that is in the Milky Way.
When you look at Image 2 of Stephan’s Quintet, a collection of five galaxies, four of which are in the process of colliding, you should be able to easily identify nearby stars by their diffraction peaks. All these stars are in the foreground of the image. The five brightly highlighted galaxies in the center (and bottom) of the image are in the middle of the image, and everything else is somewhere in the distance.
Looking through the clouds
One of the JWST’s superpowers is that it can see through the dust cloud that surrounds most galaxies. This is because the JWST sees light in the infrared part of the spectrum, and these wavelengths of light can “pierce” the cloud dust. In magnified image 3 below, we see the sharpest and sharpest view of galaxy NGC 7230, from image 2 above.
NGC 7320 is only about 40 million light-years from Earth. This image resolves more stars in NGC 7320 than Hubble could.
Compare Image 3 to the best image that was captured on Hubble (Image 4 below), and you’ll see why galaxy scientists are so excited about the potential of the JWST telescope to help advance understanding of how whose galaxies live and die.
A new vision of a stellar nursery
One of my favorite images from this first series is of the “cosmic cliffs” of the Carina Nebula. The Carina Nebula is found in the Milky Way, but can only be seen in the sky in the Southern Hemisphere. It is estimated at around 8,500 Light years From land.
While the scene in frame 5 looks like mountain cliffs at first glance, what you see is the edge of a dust cloud being pushed away by the solar winds from stars in the upper region of the frame. In the cloud are stellar nurseries where new stars form.
When a star is born, it begins to pull dust from its immediate vicinity by gravity (drawing nearby twilight) and then pushing the dust away under the pressure of its own solar wind. The JWST’s infrared view provides a more “multi-layered” view of this scene than what Hubble was able to collect in visible light.
This image is currently the desktop image on my computer because it’s so fun to watch.
See the chemical composition of other planets
The JWST does more than capture pretty images (in fact, the images it captures aren’t pretty when they come out of the telescope, NASA artists are the ones who add color to the images). A spectrograph (also sometimes called a spectrometer) is used to disperse light from an object into a spectrum, much like light through a prism.
Analyzing an object’s spectrum can tell us about its physical properties, including temperature, mass, and chemical composition. The object’s atoms and molecules actually imprint lines on its spectrum that uniquely imprint each chemical element present and can reveal a wealth of information about the object’s physical conditions. Spectroscopy and spectrometry (the sciences of interpreting these lines) allow scientists to understand what a star (or planet) is made of. (Source: From the NASA JWST website)
The spectrograph data shown below in Image 6, is the most accurate and faintest noise spectrogram of an exoplanet ever seen. For exoplanet scientists, this kind of data will provide a lifetime of information to analyze. JWST will help unravel the mysteries of other planets, stars and galaxies.
A starry swimming pool
NGC 2132 is a planetary nebula and looks like an inter-galactic pool. Although it is called a “planetary” nebula, it has nothing to do with planets. It’s a dying star, or in this case a dying binary star system.
The main image of frame 7 was taken with the JWST Near Infrared (NIRCAM) camera. Hubble also took some nice images of this nebula, but the NIRCAM on JWST is able to show it with more depth because infrared light sees deeper into the cloud surrounding the binary star system in the center.
JWST has several infrared cameras and the team wanted to test them on this target. A second image was also taken from NGC 2132 with the Mid-Infrared Camera (MIRICAM) on JWST, capturing the scene with different infrared wavelengths. Using MIRI, the team was able to resolve the binary star system (seen in the inset in Image 7). Hubble was unable to resolve this binary star system.
To infinity and beyond
The first image released by NASA from JWST was the deep-field image known as SMACS J0723.3-7327. It represents a field of vision of the universe the size of a grain of sand held at arm’s length. But your mind practically explodes when you realize how many (distant) galaxies are visible in the picture.
There’s so much to see in frame 8. Where you see the galaxies “smeared” around the center is actually light from a distant galaxy being bent by the gravity of a nearby galaxy (the white spot in the center of the image), in a phenomenon known as gravitational lensing, and predicted by Albert Einstein with his general theory of relativity.
But the real fun in Image 8 is downloading the full resolution version of the image (link), then open it in your favorite image editing application and zoom in and around the image. There are a ton of amazing things to see in the background. Good hunt!
Download NASA images
You can download any of NASA JWST images in full resolution and create your desktop image from your favorite.