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About 12 billion years ago, a dwarf galaxy known as LKH (left) collided with a young Milky Way (right) and merged with it. This artist’s concept portrays that collision. The NASA/ESA Hubble Space Telescope uncovered definitive evidence of this long-ago collision by studying ancient globular star clusters.

[Image description: An illustration of two galaxies in the midst of a collision against a dark, star-filled background. The collision takes up the middle third of the illustration. On the right, a larger galaxy is viewed at an angle from 11 o’clock to 4 o’clock, with a white-yellow core surrounded by mottled brown dust lanes and faint bluish spiral arms. To the left, a smaller, bright blue-white galaxy is stretched into a curved, hook-like shape as gravity distorts it. A broad, glowing bridge of pale blue gas and stars extends off the galaxy at the left, while wispy streams extend above and below the larger galaxy at the right. The words “Artist’s Concept” appear in the lower left corner.]

This image features data from Webb’s NIRCam (Near Infrared Camera) and MIRI (Mid Infrared Instrument) to capture the most detailed mid-infrared view yet of the field that hosts the highly evolved star IRS 3, which is located just 0.55 light-years from Sagittarius A*, the Milky Way galaxy's central supermassive black hole.

An international team of astronomers have discovered that dust and water can form and survive surprisingly close to this supermassive black hole. The observations reveal that the evolved star IRS 3 continues to enrich its surroundings with newly formed material despite the intense radiation environment around Sagittarius A*.

[Image description: A dense star field fills the entire image, with countless stars scattered across a backdrop of glowing clouds in shades of red, orange, pink, white, and blue. At the centre, a brilliant concentration of stars creates a bright, almost white core surrounded by intricate filaments and wisps of illuminated gas and dust that radiate outward. Dark, irregular patches of opaque dust interrupt the glowing clouds, particularly toward the left side of the image, where they appear as silhouetted shapes against the brighter background. The surrounding stellar population varies in brightness and colour, with cool blue stars and warmer orange and red stars distributed throughout the scene.]

Observing across the starry 'plains' of space, the NASA/ESA/CSA James Webb Space Telescope has taken images of NGC 2392, nicknamed the Lion Nebula.

The NASA/ESA Hubble Space Telescope previously viewed this planetary nebula in 2000, imaging the lion face-shaped target in visible light and revealing features such as the “mane” of hazy, comet-shaped objects. Now Webb has captured a clearer, more detailed view of the Lion Nebula due to its high-resolution imaging.

At first glance the nebula’s overall structure in Webb’s infrared images, both with the NIRCam (Near Infrared Camera) and MIRI (Mid-Infrared Instrument), may look quite similar to Hubble's earlier visible-light view. However, Webb's infrared vision highlights features like compact clumps of dust and haze of ionised gas. It’s taken several thousand years for this collection of gas and dust to reach its current shape, and the nebula’s components continue to be altered.

The source of these constant changes and the reason for the Lion Nebula’s distinct appearance is located at the centre: the remains of a dying star. Though it looks like the button nose of the lion, the central white dwarf's energy is powering the intricate structures seen here.

The bubble of ionised gas, which forms the lion’s face, is expanding over time and destroying dust that is in its path. Understanding the reason for why the swept-up gas has a complex structure of rings and shells, a common feature in planetary nebulae, is an ongoing endeavor.

The mane of the lion is the interior of a dust shell that is being illuminated by the white dwarf at the centre. The tufts of hair, which look like cometary tails of material, are compact clumps of dust that have survived the stellar core’s radiation and are protecting the material that lies behind them.

Webb’s imagery “freezes” this planetary nebula in time, though the star's death, and its tumultuous effects, go on. NGC 2392 will continue to undergo changes as its gas and dust migrate away from the stellar core. Astronomers estimate that the lion will eventually disperse in approximately 10,000 years — a relatively short period in astronomical terms.

[Image description: Planetary nebula NGC 2392, also called the Lion Nebula, against the black background of space. The nebula is in the centre, circular in shape, and looks like a male lion’s head. In the very centre is a small, pinkish-white circle with eight-point diffraction spikes, a white dwarf star. Surrounding the star are light purple-pink cavernous bubbles and shell-like rings. The bubbles and shells collectively form an oval with two small, wide arcs near the top, reminiscent of a lion’s face and its ears. What appears to be extended outward from the lion’s face is a thick ring of purple-blue material. The width of the ring is consistent throughout and resembles a mane.]

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This NASA/ESA/CSA James Webb Space Telescope Picture of the Month takes us to a fantastical realm within our home galaxy, where piercing starlight and billowing winds sculpt dust clouds into inventive shapes. This scene is from the Carina Nebula, which lies just 7500 light-years away in the constellation Carina (the Keel).

Spanning roughly 260 light-years, the nebula is home to an incredible collection of objects, including the Cosmic Cliffs revealed in the first-ever Webb image release. The Carina Nebula is also the nearest high-mass star-forming region that allows astronomers to study the full range of star formation. This nebula houses some of the most massive stars in our galaxy as well as tens of thousands of protostars, offering a valuable opportunity to understand how stars shape their neighbourhoods.

The feature highlighted in today’s image, aptly called the Treasure Chest, looks right at home in this celestial sculpture garden. The Treasure Chest is what’s known as a cometary globule. A cometary globule is an isolated cloud of gas and dust with a dense, dark head and a sweeping tail. These clouds often somewhat resemble comets, but the Treasure Chest looks distinctly like a wooden chest with its lid wide open.

However, this chest doesn’t contain jewels or gold coins, but instead a compact cluster of young stars. These stars are responsible for the otherworldly glow coming from within the Treasure Chest, revealed by Webb’s sensitive Near-Infrared Camera (NIRCam). Researchers estimate that the Treasure Chest’s cluster contains about 70 stars, the most massive of which is a rare O-type star roughly 19 times as massive as the Sun.

The star cluster is likely around 1.3 million years old, though earlier estimates found it to be as young as just 100 000 years old. Because of its youth, the cluster is still deeply embedded within the dusty clouds of the Treasure Chest. The individual stars in the cluster are wrapped up in dust as well; astronomers have found evidence that many of these stars are surrounded by circumstellar discs. Over time, the brilliant starlight from these young stars will dissipate the surrounding cloud and reveal the entire cluster.

The key to the Treasure Chest’s sculptural shape lies outside this image: just 39 light-years to the northwest, as measured on the sky, sits Eta Carinae, the most luminous object in the entire Carina Nebula. Eta Carinae is a star system containing at least two stars, one of which is 100 times as massive as the Sun. This star alone is about 5 million times as luminous as the Sun. Adding to this intense radiation is the nearby star cluster Trumpler 16, which also contains several extremely hot massive stars.

With Webb, astronomers have carried out an observing programme (#5408; PI: Reiter) dedicated to studying how young stars in the Carina Nebula collect gas from their surroundings and expel it through outflows.

[Image Description: A region of space filled with bright stars and clouds of gas. In the centre, the densest clouds form the shape of a chest with its lid open. The chest appears to glow from within. At its base it breaks apart into long pillars of thick gas. Many of the gas clouds in the background are dark orange globules, while others form large, pale hazes. A few brightly shining stars lie in the foreground, the biggest and brightest in front of the chest’s lid.]

• Release on esawebb.org