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Explanation: Put on your red/blue glasses and gaze across the western Ocean of Storms on the surface of the Moon. The 3D anaglyph shows 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: The large stellar association cataloged as NGC 206 is nestled within the dusty arms of the neighboring Andromeda galaxy along with the galaxy's pinkish star-forming regions. Also known as M31, the spiral galaxy is a mere 2.5 million light-years away. NGC 206 is found at the center of this sharp and detailed close-up of the southwestern extent of Andromeda's disk. The bright, blue stars of NGC 206 indicate its youth. In fact, its youngest massive stars are less than 10 million years old. Much larger than the open or galactic clusters of young stars in the disk of our...

Explanation: Not all those who wander are lost. A night sky example is that planets wander, and in fact the very word "planet" comes from "wandering star" in Greek. As planets shift relative to fixed stars, they may appear from our perspective to get closer to other astronomical objects. Such meetings are called conjunctions. They don't happen by chance, but follow the precise laws of celestial mechanics. This peaceful image, captured in Poland, shows the crescent Moon above the Tatra Mountains, and bright Venus close by, a little lower in the horizon. The bright star to the left of Venus...

Explanation: Don’t judge a galaxy by its size. Our home galaxy, the Milky Way, is about 100,000 light years across. This huge expanse of space contains hundreds of billions of stars! The smallest galaxies, called dwarf galaxies, are about 1/10th the size of the Milky Way and only contain a few billion stars. They are also the most common type of galaxy in the whole universe. Today’s image shows one such dwarf galaxy, NGC 4449, captured by the Hubble Space Telescope. NGC 4449 and similar dwarf galaxies are missing more oxygen than models predict. This suggests their stellar winds and...

Explanation: Sometimes Saturn disappears. It doesn't really go away, of course -- it just disappears from our view when Earth's Moon moves in front. Such a Saturnian eclipse, more formally called an occultation, was visible in early 2025 along a small swath of Earth -- from Greenland through central Europe and into northern Africa. The featured image is a digital fusion of three images, the first of just Saturn before it disappeared, and then two more of the Moon with different exposure lengths. The images were taken from Sardinia, Italy, after sunset. The bright dot near Saturn is not a...

Explanation: Does the blue nebula look like the head of a witch? The nebula is known popularly as the Witch Head Nebula because, it is said, the nebula's shape resembles a Halloween-style caricature of a witch's head. Exactly how, though, can be a topic of imaginative speculation. What is clear is that IC 2118 is about 50 light-years across and made of gas and dust that points to -- because it has been partly eroded by -- the nearby star Rigel. One of the brighter stars in the constellation Orion, Rigel lies just below the center of the featured image....

Explanation: The sky glows with soft pinkish colors of fading twilight in this serendipitous mountaintop vista. Taken in subfreezing temperatures, the thoughtfully composed photo shows snowy, rugged peaks seen from a mountain pass on 2017 November 14. Below lies the village of La Villa, Alta Badia in Italy's Dolomite Alps. Above the nestled village lights, the constellation Ursa Major hangs over the northern horizon. But most stunning is the intense fireball meteor. It was captured during the camera's exposure by chance as it flashed east to west across the northern horizon, under Ursa Major's familiar Big Dipper asterism. Sightings of...

Explanation: De Gerlache-Kocher massif looms on the visible horizon in this close-up of the edge of the Moon. The mountainous formation rises about 4 kilometers above its surroundings and is located very close to the lunar south pole. Boasting permanently shadowed crater floors that likely contain deposits of water ice and peaks that receive almost continuous sunlight for solar power generation, the south polar region is considered a prime location for the first human settlement on the Moon. In fact, De Gerlache-Kocher massif itself has been considered as a potential landing site for future crewed Artemis missions to the Moon....

Explanation: It is time to say goodbye to NASA's Neil Gehrels Swift Observatory. After nearly 22 years of service, the satellite re-entered Earth's atmosphere on November 4 at 7:39 EST over the North Sumatra region of Indonesia. The featured image is a mosaic created in 2018 using some of the first million images captured by the satellite's Ultraviolet/Optical Telescope. Swift had a combination of instruments, including an X-ray telescope and a gamma-ray telescope, that worked together to enable humanity to study, in unprecedented detail, the fastest and most energetic explosions in the universe. The most recent solar maximum accelerated the...

Explanation: One of our Solar System's most tantalizing worlds, Enceladus is backlit by the Sun in this Cassini spacecraft image from November 1, 2009. The dramatic illumination reveals the plumes that continuously spew into space from the south pole of Saturn's 500 kilometer diameter moon. Discovered by Cassini in 2005, the icy plumes are likely connected to an ocean beneath the ice shell of Enceladus. They supply material directly to Saturn's outer, tenuous E ring and make the surface of Enceladus as reflective as snow. Across the scene, Saturn's icy rings scatter sunlight toward Cassini's cameras. Beyond the rings (lower...

Explanation: “I see” IC 342, the Hidden Galaxy! Today’s image peers through the plane of the Milky Way, through all its gas, dust and stars, to unveil this spiral galaxy. IC 342 (or Caldwell 5) is one of the brightest members of the IC 342/Maffei group of galaxies. Located about 10 million light years away, this group is quite close to the Local Group that includes our Milky Way. Inaccurate accounting of the crowded and dusty Milky Way foreground has led to misunderstandings in IC 342’s history, including the theory that the galaxy was ejected from the Local Group. IC...

Explanation: Did this meteor come from that comet? Probably not. Although many meteors do originate from comets, there are thousands of comets that have visited the inner Solar System recently, and matching meteors to them can be tricky. And to be clear, the pictured comet is far behind the streaking meteor. Comet C/2025 R3 (PanSTARRS) was captured from Hautacam, France in April when the giant space iceberg sported impressive ion (blue) and dust tails. Sand-sized rocky debris that enters Earth’s atmosphere typically appears as meteors, while the colorful foreground streak here may indicate a complicated composition. This month three notable...

Explanation: What’s causing this unusually long cloud on Mars? Known as the Arsia Mons Elongated Cloud (AMEC) and first recorded by NASA’s Viking Orbiter 2 in 1977, the strange cloud has been imaged in greater detail more recently by ESA’s robotic Mars Express spacecraft. The featured image is from 2018. The cloud forms only during spring and summer seasons and then only during morning hours. Made of water-ice, the most familiar process that causes cloud crystals to form around bits of dust would fail due to the thinness and lack of dust high in the Martian atmosphere. Leading speculation holds...

Explanation: What color is the Moon? It depends on the night -- and the time. Outside of the Earth's atmosphere, the dark Moon, which shines by reflected sunlight, appears a magnificently brown-tinged gray. The featured image highlights a collection of apparent colors of the full moon on Earth, documented by one astrophotographer over 10 years from different locations across Italy. A red- or yellow-colored moon usually indicates a moon seen near the horizon. There, some of the blue light has been scattered away by a long path through the Earth's atmosphere, sometimes laden with fine dust. A blue-colored moon is...

Explanation: What spooky planet is this? Planet Earth on a dark and stormy night, of course. The ghostly scene was photographed at Hverir, a geothermally active area found along northeastern Iceland's volcanic landscape. Triggered by solar activity, geomagnetic storms have unleashed energetic particles trapped in Earth's magnetic field. Penetrating the planet's upper atmosphere at high latitudes, the particles create auroral displays in the starry night sky. Ghostly towers of steam and gas are venting from local fumaroles to dance against the eerie, greenish northern lights. For now, auroral activity on planet Earth remains in a high state as the Sun...

Explanation: Spooky shapes seem to haunt this dusty expanse, drifting through the night in the royal constellation Cepheus. Of course, the shapes are cosmic dust clouds visible in dimly reflected starlight. Far from your own neighborhood, they lurk above the plane of the Milky Way at the edge of the Cepheus Flare molecular cloud complex some 1,200 light-years away. Over 2 light-years across and brighter than most of the other ghostly apparitions, vdB 141 or Sh2-136 is also known as the Ghost Nebula. It lies at lower right in the starry field of view. Inside the Ghost Nebula are reddish...

Explanation: That's no moon. But you could be forgiven for thinking it was a crescent Moon in the sky. It is a lesser known fact that Venus also has phases. (What about other planets?) The featured image shows Venus seen almost directly between the Sun and the Earth. This happens once every year and a half, and it is like the alignment that happens every month during a new Moon. But the new Moon is dark, while Venus' backlit atmosphere refracts and scatters the sunlight, creating a glowing crescent arc that extends beyond 180 degrees: the tips of this arc...

Explanation: Jupiter is one of the least lonely planets in the Solar System, at least when it comes to natural satellites. 115 moons have been discovered orbiting Jupiter so far! (Saturn has the most with 293, but who’s counting.) Ganymede and Io, two of Jupiter’s Galilean moons, met in the sky on October 20th, 2026. Today’s video captures the meeting, with Ganymede briefly blocking Io from view. This event, when an astronomical object passes in front of another and either completely or partially blocks it, is called a mutual occultation. The mutual occultations of Galilean moons are rare to witness...

Explanation: Sometimes it's night on the ground but day in the air. As the Earth rotates to eclipse the Sun, sunset rises up from the ground. Therefore, at sunset on the ground, sunlight still shines on clouds above. Under usual circumstances, a pretty sunset might be visible, but unusual noctilucent clouds float so high up they can be seen well after dark. Normally too dim to be seen, they may become visible just after sunset during the summer when illuminated by sunlight from below the horizon. Noctilucent clouds are the highest clouds and are known more technically as polar mesospheric...

Explanation: The Great Nebula in Orion, an immense, nearby starbirth region, is one of 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 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 known...