2024 Space Telescope Advent Calendar (2025)

A Grand Spiral. The spiral galaxy NGC 5248, located 42 million light-years from Earth, is one of the so-called grand-design spirals, with prominent spiral arms that reach from near the core out through the disc. It also has a faint bar structure in the center, which is difficult to see in this visible-light portrait from the Hubble space telescope. Features like these, which break the rotational symmetry of a galaxy, can feed gas from a galaxy’s outer reaches to inner star-forming regions, and even to a galaxy’s central black hole, where it can kick-start an active galactic nucleus. These flows of gas have shaped NGC 5248 in a big way; the spiral has many bright starburst regions of intense star formation spread across its disc, and it is dominated by a population of young stars. #

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

Inside a Stellar Nursery. This image shows the center of the Serpens Nebula as seen by the James Webb Space Telescope’s Near-InfraRed Camera. The Serpens Nebula, located 1,300 light-years from Earth, is home to a particularly dense cluster of newly-forming stars, some of which will eventually grow to the mass of our Sun. Webb’s image of this nebula reveals a grouping of aligned protostellar outflows (seen in the top left). These jets are identified by bright clumpy streaks that appear red, which are shock waves caused when the jet hits the surrounding gas and dust. Throughout this image filaments and wisps of different hues represent reflected starlight from still-forming protostars within the cloud. #

NASA, ESA, CSA, STScI, K. Pontoppidan, J. Green

Ripples From a Galactic Merger. The Hubble Space Telescope brings us this nearly edge-on view of the lenticular galaxy NGC 4753. Lenticular galaxies have an elliptical shape and ill-defined spiral arms. NGC 4753 sits about 60 million light-years from Earth, and is believed to have merged with a nearby dwarf galaxy about 1.3 billion years ago, creating the distinctive wavy dust lanes around its nucleus. #

ESA / Hubble & NASA, L. Kelsey

Stormy Weather. A prominent string of alternating storms is visible across the low northern latitudes of Jupiter, forming a "vortex street" as some planetary astronomers call it. Hubble recently observed this wave pattern of nested cyclones and anticyclones, locked together like the alternating gears. If the storms get close enough to each other and merge together, they could build an even larger storm, potentially rivaling the current size of the Great Red Spot. The orange moon Io photobombs this view, casting a shadow onto Jupiter's cloudtops. For a sense of scale, Io is about one quarter of the Earth's own diameter, or just a bit larger than our own moon. #

NASA, ESA, STScI, A. Simon, M. H. Wong, J. DePasquale

Beyond the Mane. This image from the James Webb Space Telescope captures the sharpest infrared images to date of the Horsehead Nebula, and a night sky full of distant galaxies beyond. It shows a section of the sky in the constellation Orion, above the turbulent waves of dust and gas of the Horsehead nebula, otherwise known as Barnard 33, which resides roughly 1,300 light-years away. #

ESA / Webb, NASA, CSA, K. Misselt and A. Abergel

A Galactic Collision. This Hubble image features Arp 122, a galaxy that is actually made up of two vast galaxies colliding with each other—NGC 6040, the tilted, warped spiral galaxy at left, and LEDA 59642, the round, face-on spiral galaxy at right. This cosmic merger is taking place roughly 570 million light-years away from Earth, and has been unfolding over billions of years. #

ESA / Hubble & NASA, J. Dalcanton / DOE / FNAL / DECam / CTIO / NOIRLab / NSF / AURA

A Supernova Seen Thrice. NASA’s James Webb Space Telescope’s NIRCam viewed the galaxy cluster PLCK G165.7+67.0, also known as G165. In this image, a foreground cluster located 3.6 billion light-years away from Earth is magnifying and bending the light of the distant universe beyond through gravitational lensing. In this view, astronomers discovered the light of a supernova imaged three times, seen as points of light within the prominent red arc below the center of the image. To achieve three images, the light traveled along three different paths. Since each path had a different length, and light traveled at the same speed, the supernova was observed in this Webb observation at three different times during its explosion. #

NASA, ESA, CSA, STScI

A Mysterious Nebula. Details of a complex structure within the Carina Nebula (NGC 3372) are revealed by this image of the Keyhole Nebula, obtained by the Hubble Space Telescope. The picture is dominated by a large, approximately circular feature, which is part of the Keyhole Nebula. This region, about 8,000 light-years from Earth, is located adjacent to the famous explosive variable star Eta Carinae, which lies just outside the field of view toward the upper right. #

NASA, ESA, The Hubble Heritage Team

A Dark and Dusty Galaxy. This Hubble view of NGC 1546, a galaxy about 50 million light-years away, provides good view of dust lanes from slightly above and backlit by the galaxy's core. This dust absorbs light from the core, reddening it and making the dust appear rusty-brown. The core itself glows brightly in a yellowish light indicating an older population of stars. Brilliant-blue regions of active star formation sparkle through the dust. #

NASA, ESA, STScI, David Thilker

The Glow of Hot, Young Stars. The James Webb Space Telescope captured a spectacular view of the galaxy I Zwicky 18 (I Zw 18). This galaxy, roughly 59 million light-years away, is typical of the kinds of galaxies that inhabited the early Universe and it is classified as a dwarf irregular galaxy. Two major starburst regions are embedded in the heart of the galaxy. The wispy brown filaments surrounding the central starburst region are bubbles of gas that have been heated by stellar winds and intense ultraviolet radiation unleashed by hot, young stars. #

ESA / Webb, NASA, CSA, A. Hirschauer, M. Meixner

Gazing Deeply Through Time. Using the James Webb Space Telescope, an international team of astronomers detected five young massive star clusters in the Cosmic Gems arc (SPT0615-JD1), a strongly-lensed galaxy emitting light from when the Universe was roughly 460 million years old—looking back across 97% of cosmic time. #

ESA/Webb, NASA & CSA, L. Bradley, A. Adamo, and the Cosmic Spring collaboration

A Clash of Titans. This mid-infrared image of colliding galaxies IC 2163 and NGC 2207 from the James Webb Space Telescope shows two large luminous "eyes" at the galaxies’ cores, some 80 million light-years away. Webb’s mid-infrared image excels at showing where the cold dust glows throughout these galaxies—and helps pinpoint where stars and star clusters are buried within the dust. Find these regions by looking for the pink dots along the spiral arms. Many of these areas are home to actively forming stars that are still encased in the gas and dust that feeds their growth. #

NASA, ESA, CSA, STScI

A Cloud in the Deep Sky. This image featuring the central region of the Chameleon I dark molecular cloud, about 630 light years away, was taken by the James Webb Space Telescope. Cold, wispy blue clouds are illuminated in the infrared by the glow of the young, outflowing protostar Ced 110 IRS 4 (orange, upper left). The light from numerous background stars, seen as orange dots behind the cloud, can be used to detect ices in the cloud, which absorb the starlight passing through them. #

NASA, ESA, CSA, and M. Zamani

A Sky Full of Stars. The open cluster Westerlund 1 is located roughly 12,000 light-years away, residing behind a huge interstellar cloud of gas and dust. Westerlund 1, seen in this James Webb Space Telescope image, is an impressive example of a super star cluster: it contains hundreds of very massive stars, some shining with a brilliance of almost one million Suns and others two thousand times larger than the Sun (as large as the orbit of Saturn). If our Solar System was located at the heart of this remarkable cluster, our night sky would be full of hundreds of stars as bright as the full Moon. #

ESA/Webb, NASA & CSA, M. Zamani, M. G. Guarcello

Glowing From Within. This mosaic of images from the James Webb Space Telescope showcases the nearby star-forming cluster, NGC 1333, about 960 light-years away, in the Perseus molecular cloud. Across the image we see large patches of orange, which represent gas glowing in the infrared. These so-called Herbig-Haro objects form when ionized material ejected from young stars collides with the surrounding cloud—hallmarks of a very active site of star formation. Many of the young stars in this image are surrounded by discs of gas and dust, which may eventually produce planetary systems. #

ESA / Webb, NASA & CSA, A. Scholz, K. Muzic, A. Langeveld, R. Jayawardhana

A New View of a Distant Spiral. This image from the James Webb Space Telescope shows spiral galaxy NGC 628 in a new light. The galaxy, also known as Messier 74, lies about 32 million light-years away, and was first discovered in 1780. This galaxy was observed earlier this year as part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) program, a large project that includes observations from several space- and ground-based telescopes of many galaxies to help researchers study all phases of the star formation cycle. Webb's new images combining near- and mid-infrared light observations have revealed previously-unseen intricate details in the filaments, arms, and center of many galaxies. #

NASA, ESA, CSA, STScI, J. Lee, T. Williams, PHANGS Team

A Gathering of Ancient Stars. The globular cluster NGC 2005, featured in this Hubble image, is located about 750 light-years from the heart of the Large Magellanic Cloud, which is the Milky Way’s largest satellite galaxy and which itself lies about 162,000 light-years from Earth. Globular clusters are densely-packed clusters that can constitute tens of thousands or millions of stars. Their density means that they are tightly gravitationally bound and are therefore very stable. This stability contributes to their longevity: globular clusters can be billions of years old, and as such often comprise very old stars. Thus, studying globular clusters in space can be a little like studying fossils on Earth: where fossils give insights into the characteristics of ancient plants and animals, globular clusters illuminate the characteristics of ancient stars. #

ESA / Hubble & NASA, F. Niederhofer, L. Girardi

An Energetic Protostar. FS Tau is a multi-star system made up of FS Tau A, the bright star-like object near the middle of the image, and FS Tau B (Haro 6-5B), the bright object to the far right that is partially obscured by a dark, vertical lane of dust. The young objects are surrounded by softly illuminated gas and dust of this stellar nursery. The system is only about 2.8 million years old, very young for a star system. FS Tau B is a newly-forming star, or protostar, and is surrounded by a protoplanetary disc, a pancake-shaped collection of dust and gas leftover from the formation of the star that will eventually coalesce into planets. Protostars are known to eject fast-moving, column-like streams of energized material called jets, and FS Tau B provides a striking example of this phenomenon. The protostar is the source of an unusual asymmetric, double-sided jet, visible here in blue. #

NASA, ESA, K. Stapelfeldt, G. Kober

A Beacon in the Clouds. This image from the James Webb Space Telescope features a bright H II region in the Large Magellanic Cloud, a satellite galaxy of our Milky Way. This nebula, known as N79, is a region of interstellar atomic hydrogen that is ionized, seen here by Webb’s Mid-InfraRed Instrument (MIRI). N79 is a massive star-forming complex spanning roughly 1,630 light-years across. This particular image focuses on one of the three giant molecular cloud complexes, dubbed N79 South. #

ESA / Webb, NASA & CSA, O. Nayak, M. Meixner

A Galactic Chain. This Hubble image features an interacting galaxy system known as Arp-Madore 2105-332, that lies about 200 million light-years from Earth. This image also reveals several further galaxies, not associated with this system but fortuitously positioned in such a way that they appear to be forming a line that approaches the leftmost component of Arp-Madore 2105-332. #

ESA / Hubble & NASA, J. Dalcanton, Dark Energy Survey / DOE / FNAL / NOIRLab / NSF / AURA

Inside a Chaotic Nebula. Sharpless 2-106 is a nebula several light-years across, seen here by Hubble in 2011. It lies 2,000 light years away, in a relatively isolated region of the Milky Way galaxy. A massive young star is responsible for the furious activity we see inside the nebula. Twin lobes of super-hot gas, glowing blue in this image, stretch outward from the central star. A ring of dust and gas orbiting the star acts like a belt, cinching the expanding nebula into an hourglass shape. #

NASA, ESA, STScI / AURA

The Edge of a Spiral. Located roughly 150 million light-years from Earth in the constellation Serpens, UGC 10043 is one of the somewhat rare spiral galaxies that are seen edge-on. From this point of view, we see the galaxy’s disc as a sharp line through space, overlain with a prominent dust lane. One can see the lights of some active star-forming regions in the arms, shining out from behind the dust. Strikingly, we can also see that the center of the galaxy sports a glowing, almost egg-shaped ‘bulge’, rising far above and below the disc. The unusually large size of this bulge compared to the galaxy’s disc is possibly thanks to UGC 10043 siphoning material from a nearby dwarf galaxy. #

ESA / Hubble & NASA, R. Windhorst, W. Keel

A Spray of Glowing Filaments. R Aquarii is a symbiotic binary star that lies roughly 700 light-years from Earth, surrounded by a large, dynamic nebula. The primary star is an aging red giant and its companion is a compact burned-out star known as a white dwarf. When the white dwarf swings closest to the red giant along its 44-year orbital period, it gravitationally siphons off hydrogen gas. This material accumulates in the accretion disk surrounding the white dwarf, until it undergoes a powerful outburst and jet ejection. This outburst ejects powerful jets seen as filaments shooting out from the binary system, forming loops and trails as the plasma emerges in streamers. #

NASA, ESA, M. Stute, M. Karovska, D. de Martin & M. Zamani

An Energetic Stellar Nursery. This new image from the James Webb Space Telescope features the young star cluster NGC 602, surrounded by the varied clouds of a nebula, near the outskirts of the Small Magellanic Cloud, about 200,000 light-years from Earth. The existence of dark clouds of dense dust and the fact that the cluster is rich in ionized gas suggests the presence of ongoing star formation processes. #

ESA / Webb, NASA & CSA, P. Zeidler, E. Sabbi, A. Nota, M. Zamani

The Most Distant Known Galaxy. Using the James Webb Space Telescope, scientists have found a record-breaking distant galaxy observed just 290 million years after the Big Bang. In October 2023 and January 2024, an international team of astronomers used Webb to observe galaxies as part of the JWST Advanced Deep Extragalactic Survey (JADES) program, obtaining a spectrum of this record-breaking galaxy feature in this image, highlighted by the small square at center, surrounded by an ocean of thousands of other galaxies. #

NASA, ESA, CSA, STScI, J. Olmsted, S. Carniani, JADES Collaboration