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Explanation: NGC 1333 is seen in visible light as a reflection nebula, dominated by bluish hues characteristic of starlight reflected by interstellar dust. A mere 1,000 light-years distant toward the heroic constellation Perseus, it lies at the edge of a large, star-forming molecular cloud. This telescopic close-up spans over two full moons on the sky or just over 15 light-years at the estimated distance of NGC 1333. It shows details of the dusty region along with telltale hints of contrasty red emission from Herbig-Haro objects, jets and shocked glowing gas emanating from recently formed stars. In fact, NGC 1333 contains...

Explanation: Distorted galaxy NGC 2442 can be found in the southern constellation of the flying fish, (Piscis) Volans. Located about 50 million light-years away, the galaxy's two spiral arms extending from a pronounced central bar give it a hook-shaped appearance in this deep and colorful image, with foreground stars scattered across the telescopic field of view. The image also reveals the distant galaxy's obscuring dust lanes, young blue star clusters and reddish star forming regions surrounding a core of yellowish light from an older population of stars. But the star forming regions seem more concentrated along the drawn-out (upper right)...

Explanation: In the vast Orion Molecular Cloud complex, several bright blue nebulas are particularly apparent. Pictured here in the center are two of the most prominent reflection nebulas - dust clouds lit by the reflecting light of bright embedded stars. The more famous nebula is M78, in the image center, cataloged over 200 years ago. To its upper left is the lesser known NGC 2071. Astronomers continue to study these reflection nebulas to better understand how interior stars form. The overall red glow is from diffuse hydrogen gas that covers much of the Orion complex that spans much of the...

Explanation: Rising over a frozen valley in the Tatra Mountains, the familiar stars and nebulas of Orion dominate this wide-field nightscape. The featured deep photo was taken in southern Poland's highest mountain range last month, where dark skies and alpine terrain combined to reveal both Earth's rugged beauty and the structure of our galaxy. Above the snowy mountains, Orion's bright belt stars anchor a region of glowing interstellar clouds. The Great Orion Nebula, a vast stellar nursery visible even to the unaided eye, shines near the center of the scene. Surrounding it is the enormous arc of Barnard's Loop, a...

Explanation: Can you see nebulas in other galaxies? Yes, some nebulas shine brightly enough -- if you know how to look. Clouds of hydrogen and oxygen emit light at very specific colors, and by isolating them, astronomers and astrophotographers can reveal structures that would otherwise be too faint to notice. This deep, 50-hour exposure highlights glowing hydrogen (red) and oxygen (blue) across galaxy NGC 55, viewed nearly edge-on. Also known as the String of Pearls Galaxy, NGC 55 is often compared to our Milky Way's satellite galaxy the Large Magellanic Cloud (LMC), although NGC 55 lies much farther away at...

Explanation: This moon is doomed. Mars, the red planet named for the Roman god of war, has two tiny moons, Phobos and Deimos, whose names are derived from the Greek for Fear and Panic. These Martian moons may well be captured asteroids originating in the main asteroid belt between Mars and Jupiter or perhaps from even more distant reaches of our Solar System. The larger moon, Phobos, is indeed seen to be a cratered, asteroid-like object in this stunning color image from the robotic Mars Reconnaissance Orbiter, which can image objects as small as 10 meters. But Phobos orbits so...

Explanation: Eight billion people are about to disappear in this snapshot from space taken on 2022 November 21. On the sixth day of the Artemis I mission, their home world is setting behind the Moon's bright edge as viewed by an external camera on the outbound Orion spacecraft. Orion was headed for a powered flyby that took it to within 130 kilometers of the lunar surface. Velocity gained in the flyby maneuver was used to reach a distant retrograde orbit around the Moon. That orbit is considered distant because it's another 92,000 kilometers beyond the Moon, and retrograde because the...

Explanation: Very faint planetary nebula Abell 7 is about 1,800 light-years distant. It lies just south of Orion in planet Earth's skies toward the constellation Lepus, The Hare. Posing with scattered Milky Way stars, its generally simple spherical shape about 8 light-years in diameter is revealed in this deep telescopic image. The beautiful and complex shapes seen within the cosmic cloud are visually enhanced by the use of long exposures and narrowband filters that capture emission from hydrogen and oxygen atoms. Otherwise Abell 7 would be much too faint to be appreciated by eye. A planetary nebula represents a very...

Explanation: The silhouette of an intriguing dark nebula inhabits this cosmic scene. Lynds' Dark Nebula (LDN) 1622 appears against a faint background of glowing hydrogen gas only visible in long telescopic exposures of the region. In contrast, a brighter reflection nebula, vdB 62, is more easily seen just above the dusty dark nebula. LDN 1622 lies near the plane of our Milky Way Galaxy, close on the sky to Barnard's Loop, a large cloud surrounding the rich complex of emission nebulae found in the Belt and Sword of Orion. With swept-back outlines, the obscuring dust of LDN 1622 is thought...

Explanation: A mere 56 million light-years distant toward the southern constellation Fornax, NGC 1365 is an enormous barred spiral galaxy about 200,000 light-years in diameter. That's twice the size of our own barred spiral Milky Way. This sharp image from the James Webb Space Telescope's Mid-Infrared Instrument (MIRI) reveals stunning details of this magnificent spiral in infrared light. Webb's field of view stretches about 60,000 light-years across NGC 1365, exploring the galaxy's core and bright newborn star clusters. The intricate network of dusty filaments and bubbles is created by young stars along spiral arms winding from the galaxy's central bar....

Explanation: The strangest moon in the Solar System is bright yellow. The featured picture, an attempt to show how Io would appear in the "true colors" perceptible to the average human eye, was taken in 1999 July by the Galileo spacecraft that orbited Jupiter from 1995 to 2003. Io's colors derive from sulfur and molten silicate rock. The unusual surface of Io is kept very young by its system of active volcanoes. The intense tidal gravity of Jupiter stretches Io and damps wobbles caused by Jupiter's other Galilean moons. The resulting friction greatly heats Io's interior, causing molten rock to...

Explanation: What powers this unusual nebula? CTB 1 is the expanding gas shell that was left when a massive star toward the constellation of Cassiopeia exploded about 10,000 years ago. The star likely detonated when it ran out of elements, near its core, that could create stabilizing pressure with nuclear fusion. The resulting supernova remnant, nicknamed the Medulla Nebula for its brain-like shape, still glows in visible light because of the heat generated by its collision with confining interstellar gas. Why the nebula also glows in X-ray light, though, remains a topic of research. One hypothesis holds that an energetic...

Explanation: This infrared view of Jupiter by Webb is illuminating. High-resolution infrared images of Jupiter from the James Webb Space Telescope (Webb) reveal, for example, differences between high-floating bright clouds -- including the Great Red Spot -- and low-lying dark clouds. Also clearly visible in the featured Webb image are Jupiter's dust ring, bright auroras at the poles, and Jupiter's moons Amalthea and Adrastea. The footprint of large volcanic moon Io's magnetic funneling of charged particles onto Jupiter is also visible in the southern aurora. Some objects are so bright that light noticeably diffracts around Webb's optics creating streaks. Webb,...

Explanation: Apollo 14's Lunar Module Antares landed on the Moon on February 5, 1971. Toward the end of the stay astronaut Ed Mitchell snapped a series of photos of the lunar surface while looking out a window, assembled into this detailed mosaic by Apollo Lunar Surface Journal editor Eric Jones. The view looks across the Fra Mauro highlands to the northwest of the landing site after the Apollo 14 astronauts had completed their second and final walk on the Moon. Prominent in the foreground is their Modular Equipment Transporter, a two-wheeled, rickshaw-like device used to carry tools and samples. Near...

Explanation: These cosmic clouds have blossomed 1,300 light-years away in the fertile starfields of the constellation Cepheus. Called the Iris Nebula, NGC 7023 is not the only nebula to evoke the imagery of flowers. Still, this deep telescopic image shows off the Iris Nebula's range of colors and symmetries embedded in surrounding fields of interstellar dust. Within the Iris itself, dusty nebular material surrounds a hot, young star. The dominant color of the brighter reflection nebula is blue, characteristic of dust grains reflecting starlight. Central filaments of the reflection nebula glow with a faint reddish photoluminescence as some dust grains...

Explanation: The dark-floored, 95 kilometer wide crater Plato and sunlit peaks of the lunar Alps (Montes Alpes) are highlighted in this this sharp telescopic snapshot of the Moon's surface. While the Alps of planet Earth were uplifted over millions of years as continental plates slowly collided, the lunar Alps were likely formed by a sudden collision that created the giant impact basin known as the Mare Imbrium or Sea of Rains. The mare's generally smooth, lava-flooded floor is seen below the bordering mountain range. The prominent straight feature cutting through the mountains is the lunar Alpine Valley (Vallis Alpes). Joining...

Explanation: The Whirlpool Galaxy is a classic spiral galaxy. At only 30 million light years distant and fully 60 thousand light years across, M51, also known as NGC 5194, is one of the brightest and most picturesque galaxies on the sky. The featured deep image is a digital combination of images taken in different colors over 58 hours with a telescope from Lijiang, China. Anyone with a good pair of binoculars, however, can see this Whirlpool toward the constellation of the Hunting Dogs (Canes Venatici). M51 is a spiral galaxy of type Sc and is the dominant member of a...

Explanation: What just leapt from the Sun? A towering structure of solar plasma suddenly rose from the Sun's surface and unfurled into space -- a structure so large that many Earths would easily fit within it-- marking the onset of a dramatic Coronal Mass Ejection (CME). The event was captured in striking detail in late 2024 by NASA's Solar Dynamics Observatory (SDO), whose continuous monitoring improves space weather forecasts and helps humanity better understand how solar activity affects satellites, GPS, radio communications, and power grids on Earth. The featured video blends three extreme-ultraviolet views from SDO’s Atmospheric Imaging Assembly (AIA),...

Explanation: What's happening to this meteor? It is shedding its outer layers as it passes through the Earth's atmosphere and heats up. The sudden high temperatures not only cause the bright glow along the dramatic streak but also melt and vaporize the meteor's component rock and ice, creating dust. Wind in the atmosphere typically blows this dust away over the next few seconds, leaving no visible trace after only a few minutes. Much of this dust will eventually settle down to the Earth. The featured image was captured in mid-December, coincident with the Geminids meteor shower. On the upper left...

Explanation: This floating ring is the size of a galaxy. In fact, it is a galaxy -- or at least part of one: the photogenic Sombrero Galaxy, one of the largest galaxies in the nearby Virgo Cluster of Galaxies. The dark band of dust that obscures the mid-section of the Sombrero Galaxy in visible light actually glows brightly in infrared light. The featured image, digitally sharpened, shows the infrared glow, recently recorded by the orbiting Spitzer Space Telescope, superposed in false-color on an existing image taken by NASA's Hubble Space Telescope in visible light. The Sombrero Galaxy, also known as...