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Explanation: The night side of Pluto spans this shadowy scene. In the stunning spacebased perspective the Sun is 4.9 billion kilometers (almost 4.5 light-hours) behind the dim and distant world. It was captured by far flung New Horizons in July of 2015 when the spacecraft was at a range of some 21,000 kilometers from Pluto, about 19 minutes after its closest approach. A denizen of the Kuiper Belt in dramatic silhouette, the image also reveals Pluto's tenuous, surprisingly complex layers of hazy atmosphere. Near the top of the frame the crescent twilight landscape includes southern areas of nitrogen ice plains...

Explanation: Put on your red/blue glasses and gaze across the western Ocean of Storms on the surface of the Moon. The 3D anaglyph features Apollo 12 astronaut Pete Conrad visiting the Surveyor 3 spacecraft in November of 1969. Surveyor 3 had landed at the site on the inside slope of a small crater about 2 1/2 years earlier in April of 1967. Visible on the horizon beyond the far crater wall, Apollo 12's Lunar Module Intrepid touched down less than 200 meters (650 feet) away, easy moonwalking distance from the robotic Surveyor spacecraft. This stereo image was carefully created from...

Explanation: A great nebulous region near bright star omicron Persei offers this study in cosmic contrasts. Captured in the telescopic frame is a colorful complex of dust, gas, and stars spanning about 3 degrees on the sky along the edge of the Perseus molecular cloud, some 1000 light-years away. Surrounded by a bluish halo of dust-reflected starlight, omicron Persei itself is just left of center. Immediately below it lies the intriguing young star cluster IC 348 recently explored at infrared wavelengths by the James Webb Space Telescope. In silhouette against the diffuse reddish glow of hydrogen gas, dark and obscuring...

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: How was the Crescent Nebula created? Looking like an emerging space cocoon, the Crescent Nebula, visible in the center of the featured image, was created by the brightest star in its center. A leading progenitor hypothesis has the Crescent Nebula beginning to form about 250,000 years ago. At that time, the massive central star had evolved to become a Wolf-Rayet star (WR 136), shedding its outer envelope in a strong stellar wind, ejecting the equivalent of our Sun's mass every 10,000 years. This wind impacted surrounding gas left over from a previous phase, compacting it into a series of...

Explanation: What created an unusual dark streak in Comet Tsuchinshan-Atlas's tail? Some images of the bright comet during mid-October not only caught its impressively long tail and its thin anti-tail, but a rather unexpected feature: a dark streak in the long tail. The reason for the dark streak is currently unclear and a topic of some debate. Possible reasons include a plume of dark dust, different parts of the bright tail being unusually superposed, and a shadow of a dense part of the coma on smaller dust particles. The streak is visible in the featured image taken on October 14...

Explanation: The largest canyon in the Solar System cuts a wide swath across the face of Mars. Named Valles Marineris, the grand valley extends over 3,000 kilometers long, spans as much as 600 kilometers across, and delves as much as 8 kilometers deep. By comparison, the Earth's Grand Canyon in Arizona, USA is 800 kilometers long, 30 kilometers across, and 1.8 kilometers deep. The origin of the Valles Marineris remains unknown, although a leading hypothesis holds that it started as a crack billions of years ago as the planet cooled. Several geologic processes have been identified in the canyon. The...

Explanation: Ice giant Neptune is faint in Earth's night sky. Some 30 times farther from the Sun than our fair planet, telescopes are needed to catch a glimpse of the dim and distant world. This dramatic view of Neptune's night just isn't possible for telescopes in the vicinity of planet Earth though. Peering out from the inner Solar System they can only bring Neptune's day side into view. In fact this night side image with Neptune's slender crescent next to the crescent of its large moon Triton was captured by Voyager 2. Launched from planet Earth in 1977 the Voyager...

Explanation: Drifting near the plane of our Milky Way galaxy these dusty molecular clouds seem to extend a helping hand on a cosmic scale. Part of a local complex of star-forming interstellar clouds they include LDN 1358, 1357, and 1355 from American astronomer Beverly Lynds' 1962 Catalog of Dark Nebulae. Presenting a challenging target for astro-imagers, the obscuring dark nebulae are nearly 3,000 light-years away, toward rich starfields in the northern constellation Cassiopeia. At that distance, this deep, telescopic field of view would span about 80 light-years.

Explanation: This spectacular intergalactic skyscape features Arp 227, a curious system of galaxies from the 1966 Atlas of Peculiar Galaxies. Some 100 million light-years distant within the boundaries of the constellation Pisces, Arp 227 consists of the two galaxies prominent above and left of center, the shell galaxy NGC 474 and its blue, spiral-armed neighbor NGC 470. The readily apparent shells and star streams of NGC 474 are likely tidal features originating from the accretion of another smaller galaxy during close gravitational encounters that began over a billion years ago. The large galaxy on the bottom righthand side of the...

Explanation: Comet Tsuchinshan-Atlas is now headed back to the outer Solar System. The massive dusty snowball put on quite a show during its trip near the Sun, resulting in many impressive pictures from planet Earth during October. The featured image was taken in mid-October and shows a defining visual feature of the comet -- its impressive anti-tail. The image captures Comet C/2023 A3 (Tsuchinshan–ATLAS) with impressively long dust and ion tails pointing up and away from the Sun, while the strong anti-tail -- composed of more massive dust particles -- trails the comet and points down and (nearly) toward the...

Explanation: Why were the statues on Easter Island built? No one is sure. What is sure is that over 900 large stone statues called moais exist there. The Rapa Nui (Easter Island) moais stand, on average, over twice as tall as a person and have over 200 times as much mass. It is thought that the unusual statues were created about 600 years ago in the images of local leaders of a vibrant and ancient civilization. Rapa Nui has been declared by UNESCO to a World Heritage Site. Pictured here, some of the stone giants were imaged last month under...

Explanation: The Great Nebula in Orion, an immense, nearby starbirth region, is probably the most famous of all astronomical nebulas. Here, glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1500 light-years away. In the featured deep image in assigned colors highlighted by emission in oxygen and hydrogen, wisps and sheets of dust and gas are particularly evident. The Great Nebula in Orion can be found with the unaided eye near the easily identifiable belt of three stars in the popular constellation Orion. In addition to housing a bright open cluster of stars...

Explanation: What's that black spot on Jupiter? No one is sure. During one pass of NASA's Juno over Jupiter, the robotic spacecraft imaged an usually dark cloud feature informally dubbed the Abyss. Surrounding cloud patterns show the Abyss to be at the center of a vortex. Since dark features on Jupiter's atmosphere tend to run deeper than light features, the Abyss may really be the deep hole that it appears -- but without more evidence that remains conjecture. The Abyss is surrounded by a complex of meandering clouds and other swirling storm systems, some of which are topped by light...

Explanation: Saturn is bright in Earth's night skies. Telescopic views of the outer gas giant planet and its beautiful rings often make it a star at star parties. But this stunning view of Saturn's rings and night side just isn't possible from telescopes in the vicinity of planet Earth. Peering out from the inner Solar System they can only bring Saturn's day side into view. In fact, this image of Saturn's slender sunlit crescent with night's shadow cast across its broad and complex ring system was captured by the Cassini spacecraft. A robot spacecraft from planet Earth, Cassini called Saturn...

Explanation: Big, beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across, larger than our own Milky Way. It lies some 30 million light-years distant in the southern constellation Pavo but appears as only a faint smudge in the eyepiece of a small telescope. We see the disk of the nearby island universe tilted towards our line of sight in this remarkably deep and detailed galaxy portrait, a telescopic image that spans an area about the angular size of a full moon. In it, the giant galaxy's elongated yellowish core is dominated by the light from old, cool stars. Beyond...

Explanation: By starlight, this eerie visage shines in the dark with a crooked profile evoking its popular name, the Witch Head Nebula. In fact, this entrancing telescopic portrait gives the impression that a witch has fixed her gaze on Orion's bright supergiant star Rigel. More formally known as IC 2118, the Witch Head Nebula spans about 50 light-years and is composed of interstellar dust grains reflecting Rigel's starlight. The color of the Witch Head Nebula is caused not only by Rigel's intense blue light, but because the dust grains scatter blue light more efficiently than red. The same physical process...

Explanation: What created this huge space bubble? Blown by the wind from a star, this tantalizing, head-like apparition is cataloged as NGC 7635, but known simply as the Bubble Nebula. The featured striking view utilizes a long exposure to reveal the intricate details of this cosmic bubble and its environment. Although it looks delicate, the 10 light-year diameter bubble offers evidence of violent processes at work. Seen here above and right of the Bubble's center, a bright hot star is embedded in the nebula's reflecting dust. A fierce stellar wind and intense radiation from the star, which likely has a...

Explanation: The stars are destroying the pillars. More specifically, some of the newly formed stars in the image center are emitting light so energetic that is evaporating the gas and dust in the surrounding pillars. Simultaneously, the pillars themselves are still trying to form new stars. The whole setting is the star cluster NGC 602, and this new vista was taken by the Webb Space Telescope in multiple infrared colors. In comparison, a roll-over image shows the same star cluster in visible light, taken previously by the Hubble Space Telescope. NGC 602 is located near the perimeter of the Small...

Explanation: Sometimes a river of hot gas flows over your head. In this case the river created a Strong Thermal Emission Velocity Enhancement (STEVE) that glowed bright red, white, and pink. Details of how STEVEs work remain a topic of research, but recent evidence holds that their glow results from a fast-moving river of hot ions flowing over a hundred kilometers up in the Earth's atmosphere: the ionosphere. The more expansive dull red glow might be related to the flowing STEVE, but alternatively might be a Stable Auroral Red (SAR) arc, a more general heat-related glow. The featured picture, taken...