10 times this year the Webb telescope has baffled astronomers with stunning new images of our universe

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By Colin Jacobs and Carl Glazebrook, Swinburne University of Technology, December 29, 2022

What looks a lot like rocky mountains on a moonlit evening is actually the edge of the nearby, young star-forming region NGC 3324 in the Carina Nebula. Taken in infrared light by the Near Infrared Camera (NIRCam) on NASA’s James Webb Space Telescope, this image reveals previously obscured regions of star birth. Credit: NASA, ESA, CSA, STScI

It is no exaggeration to say that the James Webb Space Telescope (JWST) marks a new era for modern astronomy.

The telescope was launched on December 25 of last year and has been fully operational since July, offering glimpses of the universe that we have never had access to before. Like the Hubble Space Telescope, the JWST is in space, so it can capture images in stunning detail free from the distortions of Earth’s atmosphere.

However, while Hubble is in Earth orbit at an altitude of 335 miles (540 km), JWST is 1 million miles (1.5 million km) away from the Moon. From this location, far from overlapping our planet’s reflected heat, it can collect light from across the universe far in the infrared portion of the electromagnetic spectrum.

This ability, when combined with JWST’s larger mirror, state-of-the-art detectors and many other technological advances, allows astronomers to look back to the earliest ages of the universe.

As the universe expands, it stretches the wavelength of light heading toward us, making distant objects appear redder. At large enough distances, the light from the galaxy travels entirely outside the visible part of the electromagnetic spectrum and into the infrared. The JWST is able to probe these light sources back to the earliest times, roughly 14 billion years ago.

The Hubble Telescope is still a great science instrument and can see in wavelengths of light where the JWST telescope cannot. But Webb’s telescope can see further into the infrared with greater sensitivity and clarity.

Let’s take a look at ten images that show the amazing power of this new window on the universe.

1. Mirror alignment is complete

Left: The first publicly released alignment image from JWST. Astronomers jumped on this image to compare it to previous images of the same part of the sky as the one on the right from the Earth’s Dark Energy Camera. Credit: NASA/STScI/LegacySurvey/C. Jacobs

Despite years of testing on Earth, a complex observatory like JWST requires extensive configuration and testing once it is deployed in the cold and dark space.

One of the biggest tasks was to open 18 hexagonal segments of the mirror and align a small part of the wavelength of light. In March, NASA released the first image (star-centered) from the fully aligned mirror. Even though it was just a calibration image, astronomers immediately compared it to existing images of that patch of sky—with great excitement.

2. Spitzer vs. Merry

This image shows part of the Pillars of Creation in infrared (see below); On the left it was taken by the Spitzer Space Telescope and JWST on the right. The contrast in depth and resolution is dramatic. Credit: NASA/JPL-Caltech (left), NASA/ESA/CSA/STScI (right)

This early image, taken while all cameras were focused, clearly demonstrates the gradual change in data quality that JWST offers over its predecessors.

On the left is an image from the Spitzer Space Telescope Infrared Observatory with an 85 cm mirror; On the right, the same field from JWST’s MIRI medium infrared camera and 6.5-meter mirror. The resolution and ability to spot lots of fainter sources is on display here, with hundreds of galaxies lost in the noise of the Spitzer image visible. This is what a larger mirror, located in the deepest and coldest darkness, can do.

3. The first image of a galaxy cluster

Galaxy cluster SMACS 0723 – from Hubble on the left and JWST on the right. Hundreds of other galaxies appear in JWST’s infrared image. Credit: NASA/STSci

The galaxy cluster with the typology SMACS J0723.3–7327 was a good choice for the first publicly released color images from JWST.

The field is crowded with galaxies of all shapes and colours. The combined mass of this massive galaxy cluster, more than 4 billion light-years away, curves space in such a way that light from distant background sources is stretched and amplified, an effect known as gravitational lensing.

These distorted background galaxies can be clearly seen as lines and arcs throughout this image. This field is already striking in Hubble images (left), but JWST’s near-infrared image (right) reveals a wealth of additional detail, including hundreds of distant galaxies too faint or too red to be detected by its predecessor.

4. Stefan’s Quintet

Hubble (left) and JWST (right) images of the galaxy group known as the “Stefan Quintet”. The inset shows a zoom in on a distant background galaxy. Credit: NASA/STScI

These images depict a stunning group of galaxies known as Stephan’s Quintet, a group that has long been of interest to astronomers who study the way colliding galaxies interact with each other via gravity.

On the left is the Hubble view, and on the right is the JWST mid-infrared view. The inset shows the power of the new telescope, with a zoom in on a small background galaxy. In the Hubble image, we see some bright star-forming regions, but only with JWST does the full structure of these and surrounding galaxies reveal itself.

5. Pillars of Creation

The Pillars of Creation, a star-forming region in our galaxy, as captured by Hubble (left) and JWST (right). Credit: NASA, ESA, CSA, STScI; Joseph DiPasquale (STScI), Anton M Coquemore (STScI), Alyssa Pagan (STScI).

The so-called Pillars of Creation is one of the most iconic images in all of astronomy, taken by Hubble in 1995. It showed the space telescope’s extraordinary reach.

It depicts a star-forming region in the Eagle Nebula, where interstellar dust and gas provide the backdrop for a stellar nursery teeming with new stars. The image at right, captured with JWST’s Near Infrared Camera (NIRCam), shows an additional advantage of infrared astronomy: the ability to peer through the shroud of dust and see what lies within and behind it.

6. Protostar “Hourglass”

An “hourglass protostar”, a star that is still in the process of creating enough gas to start hydrogen fusion. Inset: displaying a significantly lower resolution than Spitzer. Credit: NASA/STScI/JPL-Caltech/A. Tobin

This image depicts another act of galactic creation within the Milky Way. This hourglass-shaped structure is a cloud of dust and gas surrounding a star in the process of formation — a protostar called L1527.

Visible only in infrared, an “accretion disc” of the material that falls (the black bar in the center) will eventually enable the protostar to gather enough mass to begin hydrogen fusion, and a new star will be born.

Meanwhile, light from the still-forming star illuminates the gas above and below the disk, creating an hourglass shape. Our earlier view of this came from Spitzer. The amount of detail is again a huge leap forward.

7. Jupiter in the infrared

Infrared view of Jupiter from JWST. Note the auroral glow at the poles; This is caused by the interaction of charged particles from the Sun with Jupiter’s magnetic field. Credit: NASA, ESA, CSA, Jupiter ERS Team; Image processing by Judy Schmidt.

The Webb telescope’s mission involves imaging galaxies farthest from the beginning of the universe, but they can look a little closer to their home as well.

Although JWST can’t look out at Earth or the inner planets of the solar system—as they must always be farther from the sun—it can look outward to the more distant parts of our solar system. This near-infrared image of Jupiter is a beautiful example, as we stare deeply into the gas giant’s cloud and storm structure. The glow of the Northern Lights at the North and South Poles is painful.

This image was extremely difficult to obtain due to Jupiter’s rapid movement across the sky relative to the stars and its rapid rotation. The success demonstrated the Webb telescope’s ability to track difficult astronomical targets very well.

8. The Phantom Galaxy

Hubble visible-light (left), JWST infrared (right), and (middle) combined images of ‘Phantom Galaxy’ M74. The ability to combine visible-light information about stars with infrared images of gas and dust allows us to explore these galaxies in exquisite detail. Credit: ESA/Webb, NASA, CSA, J. Lee and the PHANGS-JWST Team; ESA/Hubble & NASA, R. Chandar Acknowledgments: J. Schmidt

These images of the so-called Phantom Galaxy, or M74, reveal the power of JWST not only as the latest and greatest of astronomical instruments, but as a valuable complement to other great instruments. The middle panel here combines visible light from Hubble and infrared light from Webb, allowing us to see how starlight (via Hubble) and gas and dust (via JWST) together form this fascinating galaxy.

Much of JWST’s science is designed to be combined with Hubble’s optical views and other imaging to take advantage of this principle.

9. A galaxy far, far away

“Zoom in” a galaxy from one of the early ages of the universe, when the universe was only about 300 million years old (small red source visible in center right panel). It is impossible to detect galaxies at this distance in visible light since their emitted radiation is “redshifted” far in the infrared. Credit: NASA/STScI/C. Jacobs

Although this galaxy – the small red dot in the right image – is not among the most amazing galaxies the universe has to offer, it is interesting from a scientific point of view.

This snapshot is from when the universe was only 350 million years old, making it one of the first galaxies ever to form. Understanding the details of how these galaxies grew and merged to form galaxies like our own Milky Way 13 billion years later is a major question, and one with many remaining mysteries, which makes discoveries like this much needed.

It is also a view that only JWST can achieve. Astronomers didn’t quite know what to expect; An image of this galaxy taken by Hubble will appear empty, as the galaxy’s light is stretched far in the infrared due to the expansion of the universe.

10. This giant mosaic is Label 2744

Image of galaxy cluster Abell 2744 created by combining several different JWST exposures. In this small part of the sky (a small part of the full moon), every one of the thousands of visible objects is a galaxy far, far away. Image credit: Lukas Furtak (Ben-Gurion University of the Negev) via photos from the GLASS/UNCOVER teams

This image is a mosaic (many individual images strung together) centered around the giant Abell 2744 galaxy cluster, colloquially known as the “Pandora’s Cluster.” The sheer number and variety of sources that JWST can detect is mind-boggling; With the exception of a few foreground stars, each spot of light represents an entire galaxy.

In a patch of dark sky no larger than a fraction the size of the full moon, there are countless thousands of galaxies, which truly recreates the colossal scale of the universe in which we live. Professional and amateur astronomers alike can spend hours poring over this image for oddities and mysteries.

Over the coming years, JWST’s ability to look deeply and far back into the universe will allow us to answer many questions about how we came to be. The discoveries and questions we can’t yet anticipate are just as exciting. When you remove the veil of time as only this new telescope does, these unknowns are sure to be fascinating.

written by:

Colin Jacobs – Postdoctoral Researcher in Astrophysics, Swinburne University of Technology Carl Glazebrook – ARC Prize Laureate Fellow and Distinguished Professor, Center for Astrophysics and Supercomputing, Swinburne University of Technology

This article was first published in The Conversation.

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