Barred Spiral Galaxy NGC 646 by Euclid

Click the image for higher resolution (6.0 MB)

Galaxy NGC 646 sparkles like a cosmic holiday garland in this new image from the European Space Agency's Euclid space telescope. This large barred spiral galaxy is located in the constellation Hydrus and was discovered in 1834 by the British astronomer John Herschel (the son of William Herschel). The galaxy is moving away from us at about 8145 km per second. It's located roughly 392 million light-years from Earth, which means its light takes hundreds of millions of years to reach us. Although this sounds very far, NGC 646 is actually quite close compared to the billions of galaxies that Euclid will observe during its six-year mission.

By the end of 2026, ESA and the Euclid Consortium will release the first year of observations, covering about 1900 square degrees of the sky (approximately 14% of the total survey area). These images will reveal hundreds of thousands of galaxies in exquisite detail, offering new insights into how galaxies form and evolve – and why barred galaxies become more common as the Universe ages.

In this image, NGC 646 appears close to a smaller galaxy to the left, called PGC 6014. They look like neighbours, but they're actually about 45 million light-years apart, with PGC 6014 at a distance of 347 million light-years from us. So, any gravitational interaction between them, if it exists, would be very weak and short-lived. Image Credit: ESA/Euclid/Euclid Consortium/NASA

Image processing by the Euclid Science Ground Segment and M. Schirmer (MPIA)

Image enhancement: Jean-Baptiste Faure

Star-Forming Region Sagittarius B2 by Webb

Click the image for higher resolution (4.8 MB)

Stars, gas and cosmic dust in the Sagittarius B2 molecular cloud glow in near-infrared light, captured by Webb's NIRCam (Near-Infrared Camera). In this light, astronomers see more of the region's diverse, colourful stars, but less of its gas and dust structure. Webb's instruments each provide astronomers with important information that help build a more complete picture of what is happening in this intriguing portion of the centre of our galaxy.

Sagittarius B2 is the Milky Way galaxy's most massive and active star forming cloud, producing half of the stars created in the galactic center region despite having only 10 percent of the area's star-making material. Now, Webb has revealed stunning new views of the region, using both its near-infrared and mid-infrared instruments, to capture both its colourful stars and gaseous stellar nurseries in unprecedented detail.

Sagittarius B2 is located only a few hundred light-years from the supermassive black hole at the heart of the galaxy called Sagittarius A, a region densely packed with stars, star-forming clouds, and complex magnetic fields. The infrared light that Webb detects is able to pass through some of the area's thick clouds to reveal young stars and the warm dust surrounding them. Astronomers think that analysis of Webb's data will help unravel enduring mysteries of the star formation process, and why Sagittarius B2 is forming so many more stars than the rest of the galactic center.

However, one of the most notable aspects of Webb's images of Sagittarius B2 are the portions that remain dark. These ironically empty-looking areas of space are actually so dense with gas and dust that even Webb cannot see through them. These thick clouds are the raw material of future stars and a cocoon for those still too young to shine.

Image Credit: NASA, ESA, CSA, STScI, A. Ginsburg (University of Florida); Image Processing: A. Pagan (STScI)

Image enhancement: Jean-Baptiste Faure

Galaxy Cluster Abell S1063 as seen by Webb

Click the image for higher resolution (11.3 MB)

The eye is first drawn, in this James Webb Space Telescope picture, to the central mega-monster that is galaxy cluster Abell S1063. This behemoth collection of galaxies, lying 4.5 billion light-years from Earth in the constellation Grus (the Crane), dominates the scene. Looking more closely, this dense collection of heavy galaxies is surrounded by glowing streaks of light, and these warped arcs are the true object of scientists’ interest: faint galaxies from the Universe's distant past.

Abell S1063 was previously observed by the Hubble Space Telescope's Frontier Fields programme. It is a strong gravitational lens: the galaxy cluster is so massive that the light of distant galaxies aligned behind it is bent around it, creating the warped arcs that we see here. Like a glass lens, it focuses the light from these faraway galaxies. The resulting images, albeit distorted, are both bright and magnified — enough to be observed and studied. This was the aim of Hubble’s observations, using the galaxy cluster as a magnifying glass to investigate the early Universe.

The new imagery from Webb's Near-Infrared Camera (NIRCam) takes this quest even further back in time. This image showcases an incredible forest of lensing arcs around Abell S1063, which reveal distorted background galaxies at a range of cosmic distances, along with a multitude of faint galaxies and previously unseen features.

This image is what's known as a deep field – a long exposure of a single area of the sky, collecting as much light as possible to draw out the most faint and distant galaxies that don't appear in ordinary images. With 9 separate snapshots of different near-infrared wavelengths of light, totalling around 120 hours of observing time and aided by the magnifying effect of gravitational lensing, this is Webb's deepest gaze on a single target to date. Focusing such observing power on a massive gravitational lens, like Abell S1063, therefore has the potential to reveal some of the very first galaxies formed in the early Universe.

The observing programme that produced this data, GLIMPSE, aims to probe the period known as Cosmic Dawn, when the Universe was only a few million years old. Studying the galaxies revealed by gravitational lensing has the potential to develop our understanding of the emergence of the first galaxies. Analysis of this NIRCam data by the GLIMPSE team has already produced candidates for galaxies that existed as early as 200 million years after the Big Bang, and hints of the elusive first population of stars in the Universe.

Image Credit: ESA/Webb, NASA and CSA, H. Atek, M. Zamani (ESA/Webb)

Acknowledgement: R. Endsley

Image enhancement: Jean-Baptiste Faure

Spiral Galaxy NGC 4571

Click the image for higher resolution (8.4 MB)

A star-studded spiral galaxy shines in this Hubble Space Telescope picture. This galaxy is called NGC 4571, and it's situated about 60 million light-years away in the constellation Coma Berenices. NGC 4571 dominates the scene with its feathery spiral structure and sparkling star clusters.

The galaxy's dusty spiral arms are dotted with brilliant pink nebulae that contain massive young stars. Though the star-forming clouds that are seen here are heated to roughly 10 000 degrees by searing ultraviolet light from the young stars at their cores, stars get their start in much chillier environments. The sites of star birth are giant molecular clouds tens to hundreds of light-years across, in which the temperature hovers just a few tens of degrees above absolute zero.

The dramatic transformation from freezing gas cloud to fiery young star happens thanks to the immense pull of gravity, which collects gas into dense clumps within a star-forming cloud. As these clumps yield to gravity's pull and collapse inward, they eventually become hot and dense enough to spark nuclear fusion in their centers and begin to shine. The glowing clouds in this image surround particularly massive stars that are hot enough to ionise the gas of their birthplaces.

A Hubble image of NGC 4571 was previously released in 2022, using data from an observing programme the combines data from leading observatories like Hubble, the James Webb Space Telescope, and the Atacama Large Millimeter/submillimeter Array to study star formation in nearby spiral galaxies like NGC 4571. The new image released today adds data from a programme that seeks to understand how dust affects our observations of young stars deeply embedded within their natal clouds.

Image Credit: ESA/Hubble and NASA, F. Belfiore, J. Lee and the PHANGS-HST Team

Image enhancement: Jean-Baptiste Faure

Planetary Nebula NGC 6537 as seen by Webb

Click the image for higher resolution (9.8 MB)

This new James Webb Space Telescope picture features a cosmic creepy-crawly called NGC 6537 – the Red Spider Nebula. Using its Near-InfraRed Camera (NIRCam), Webb has revealed never-before-seen details in this picturesque planetary nebula with a rich backdrop of thousands of stars.

Planetary nebulae like the Red Spider Nebula form when ordinary stars like the Sun reach the end of their lives. After ballooning into cool red giants, these stars shed their outer layers and cast them into space, exposing their white-hot cores. Ultraviolet light from the central star ionises the cast-off material, causing it to glow. The planetary nebula phase of a star's life is as fleeting as it is beautiful, lasting only a few tens of thousands of years.

The central star of the Red Spider Nebula is visible in this image, glowing just brighter than the webs of dusty gas that surround it. The surprising nature of the nebula's tremendously hot and luminous central star has been revealed by Webb's NIRCam. In optical-wavelength images, such as from the Hubble Space Telescope, the star appears faint and blue. But in the NIRCam images, it shows up as red: thanks to its sensitive near-infrared capabilities, Webb has revealed a shroud of hot dust surrounding the central star. This hot dust likely orbits the central star, in a disc structure.

Though only a single star is visible in the Red Spider's heart, a hidden companion star may lurk there as well. A stellar companion could explain the nebula's shape, including its characteristic narrow waist and wide outflows. This hourglass shape is seen in other planetary nebulae such as the Butterfly Nebula, which Webb also recently observed.

Webb's new view of the Red Spider Nebula reveals for the first time the full extent of the nebula's outstretched lobes, which form the "legs" of the spider. These lobes, shown in blue, are traced by light emitted from H2 molecules, which contain two hydrogen atoms bonded together. Stretching over the entirety of NIRCam's field of view, these lobes are shown to be closed, bubble-like structures that each extend about 3 light-years. Outflowing gas from the centre of the nebula has inflated these massive bubbles over thousands of years.

Gas is also actively jetting out from the nebula's center, as these new Webb observations show. An elongated purple "S" shape centred on the heart of the nebula follows the light from ionised iron atoms. This feature marks where a fast-moving jet has emerged from near the nebula's central star and collided with material that was previously cast away by the star, sculpting the rippling structure of the nebula seen today.

The observations used to create this image come from Webb GO programme #4571 (PI: J. Kastner) as part of a joint Chandra-JWST observing programme, which aims to understand how bipolar planetary nebulae like the Red Spider Nebula are shaped by the outflows and jets that emerge from the stars at their cores.

Image Credit: ESA/Webb, NASA and CSA, J. H. Kastner (Rochester Institute of Technology)

Image enhancement: Jean-Baptiste Faure

Dwarf Galaxies NGC 4490 and NGC 4485 by Webb

Click the image for higher resolution (12.3 MB)

For this new Webb picture, the James Webb Space Telescope has spied a pair of dwarf galaxies engaged in a gravitational dance. These two galaxies are named NGC 4490 and NGC 4485, and they're located about 24 million light-years away in the constellation Canes Venatici (The Hunting Dogs). Aside from the Milky Way's own dwarf companions (the Large and Small Magellanic Clouds), this is the closest known interacting dwarf-dwarf system where astronomers have directly observed both a gas bridge and resolved stellar populations. Together NGC 4490 and NGC 4485 form the system Arp 269, which is featured in the Atlas of Peculiar Galaxies. At such a close distance (and with Webb's impressive ability to peer through dusty cosmic clouds) these galaxies allow astronomers to witness up close the kinds of galaxy interactions that were common billions of years ago.

Dwarf galaxies likely share many similarities with young galaxies in the early Universe: they are much less massive than galaxies like the Milky Way, they typically have small amounts of metals (what astronomers call elements heavier than helium), and they contain a lot of gas and relatively few stars. When nearby dwarf galaxies collide, merge, or steal gas from one another, it can tell us how galaxies billions of years ago might have grown and evolved.

The nearby dwarf galaxies NGC 4490 and NGC 4485 form an intriguing pair. Nearly three decades ago, astronomers discovered a wispy bridge of gas connecting the two galaxies, showing that they have interacted in the past. Despite many studies with powerful telescopes like the Hubble Space Telescope, the history between NGC4490 and NGC 4485 has remained mysterious.

Recently, Webb observed this curious galactic pair as part of the Feedback in Emerging extrAgalactic Star clusTers (FEAST) programme (#1783; PI: A. Adamo). The FEAST programme used Webb's sensitive infrared eyes to reveal the formation of new stars in different types of nearby galaxies.

This image was developed using data from Webb's Near-InfraRed Camera (NIRCam) and Mid-InfraRed Instrument (MIRI), as well as a single narrow-band filter from Hubble (657N). It reveals NGC 4490 and NGC 4485 in never-before-seen detail and illuminates the bridge of gas and stars that connects them. NGC 4490 dominates the image as the larger object occupying the left side of the image, while NGC 4485 is the smaller galaxy that hosts the top-right portion of the image. By dissecting these galaxies star by star, researchers were able to map out where young, middle-aged, and old stars reside, and trace the timeline of the galaxies' interaction.

Roughly 200 million years ago, these galaxies whirled close to one another before waltzing away. The larger galaxy, NGC 4490, ensnared a stream of gas from its companion, and this gas now trails between the galaxies like dancers connected by outstretched arms. Along the newly formed bridge of gas and within the two galaxies, this interaction spurred a burst of new stars. The concentrated areas of bright blue that appear throughout the field indicate highly ionised regions of gas by the recently formed star clusters. Just 30 million years ago, these galaxies burst alight with stars once more, with new clusters coalescing where the gas of the two galaxies mixed together.

By capturing the history of the galactic dancers NGC 4490 and NGC 4485, Webb has revealed new details in how dwarf galaxies interact, giving us a glimpse of how small galaxies near and far grow and evolve.

Image Credit: ESA/Webb, NASA and CSA, A. Adamo (Stockholm University), G. Bortolini, and the FEAST JWST team

Image enhancement: Jean-Baptiste Faure

The Virgo Cluster as seen by Rubin

Click the image for higher resolution (5.0 MB)

This image captures a small section of NSF–DOE Vera C. Rubin Observatory's view of the Virgo Cluster, revealing both the grand scale and the faint details of this dynamic region of the cosmos. Bright stars from our own Milky Way shine in the foreground, while a sea of distant reddish galaxies speckle the background.

Image Credit: NSF–DOE Vera C. Rubin Observatory

Image enhancement: Jean-Baptiste Faure