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Explanation: Similar in size to large, bright spiral galaxies in our neighborhood, IC 342 is a mere 10 million light-years distant toward the long-necked, northern constellation Camelopardalis. A sprawling island universe, IC 342 would otherwise be a prominent galaxy in our night sky, but it is hidden from clear view and only glimpsed through the veil of stars, gas and dust clouds along the plane of our own Milky Way galaxy. Even though IC 342's light is dimmed and reddened by intervening cosmic clouds, this sharp telescopic image traces the galaxy's own obscuring dust, young star clusters, and glowing star...

Explanation: Its popular nickname is the Spaghetti Nebula. Officially cataloged as Simeis 147 and Sharpless 2-240, it is easy to get lost following the looping and twisting filaments of this intricate supernova remnant. Seen toward the boundary of the constellations of the Bull (Taurus) and the Charioteer (Auriga), the impressive gas structure covers nearly 3 degrees on the sky, equivalent to 6 full moons. That's about 150 light-years at the stellar debris cloud's estimated distance of 3,000 light-years. The supernova remnant has an estimated age of about 40,000 years, meaning light from this powerful stellar explosion first reached the Earth...

Explanation: How complex is Jupiter? NASA's Juno mission to Jupiter is finding the Jovian giant to be more complicated than expected. Jupiter's magnetic field has been discovered to be much different from our Earth's simple dipole field, showing several poles embedded in a complicated network more convoluted in the north than the south. Further, Juno's radio measurements show that Jupiter's atmosphere shows structure well below the upper cloud deck -- even hundreds of kilometers deep. Jupiter's newfound complexity is evident also in southern clouds, as shown in the texture and color enhanced featured image taken last month. There, planet-circling zones...

Explanation: How was the unusual Red Rectangle nebula created? At the nebula's center is an aging binary star system that surely powers the nebula but does not, as yet, explain its colors. The unusual shape of the Red Rectangle is likely due to a thick dust torus which pinches the otherwise spherical outflow into tip-touching cone shapes. Because we view the torus edge-on, the boundary edges of the cone shapes seem to form an X. The distinct rungs suggest the outflow occurs in fits and starts. The unusual colors of the nebula are less well understood, however, and speculation holds...

Explanation: Most galaxies have a single nucleus -- does this galaxy have four? The strange answer leads astronomers to conclude that the nucleus of the surrounding galaxy is not even visible in this image. The central cloverleaf is rather light emitted from a background quasar. The gravitational field of the visible foreground galaxy breaks light from this distant quasar into four distinct images. The quasar must be properly aligned behind the center of a massive galaxy for a mirage like this to be evident. The general effect is known as gravitational lensing, and this specific case is known as the...

Explanation: The Full Moon is the brightest lunar phase, and tonight you can stand in the light of the first Full Moon of 2026. In fact, the Moon's full phase occurs on January 3 at 10:03 UTC, while only about 7 hours later planet Earth reaches its 2026 perihelion, the closest point in its elliptical orbit around the Sun, at 17:16 UTC. January's Full Moon was also not far from its own perigee, or closest approach to planet Earth. For this lunation the Moon's perigee was on January 1 at 21:44 UTC. You can also spot planet Jupiter, near its...

Explanation: In 2011, on January 20, NASA's NanoSail-D2 unfurled a very thin and very reflective 10 square meter sail becoming the first solar sail spacecraft in low Earth orbit. Often considered the stuff of science fiction, sailing through space was suggested 400 years ago by astronomer Johannes Kepler, who had observed comet tails blown by the solar wind. But modern solar sail spacecraft designs, like NanoSail-D2, Japan's interplanetary spacecraft IKAROS, or the Planetary Society's Lightsail A, rely on the small but continuous pressure from sunlight itself for thrust. Glinting in the sunlight as it circled planet Earth, NanoSail-D2's solar sail...

Explanation: Cycle 25 solar maximum made 2025 a great year for aurora borealis (or aurora australis) on planet Earth. And the high level of solar activity should extend into 2026. So, while you're celebrating the arrival of the new year, check out this spectacular auroral display that erupted in starry night skies over Kirkjufell, Iceland. The awesome auroral corona, energetic curtains of light streaming from directly overhead, was witnessed during a strong geomagnetic storm triggered by intense solar activity near the March 2025 equinox. This boreal skyscape captures the evocative display in a 21 frame panoramic mosaic.

Explanation: What created the Waterfall Nebula? The origin is still being researched. The structure, officially designated Herbig-Haro 222, appears in the region of NGC 1999 in the Great Orion Molecular Cloud complex. The elongated gaseous stream stretches about ten light years but appears similar to a long waterfall on Earth. Recent observations indicate that HH-222 is likely a gigantic gaseous bow shock, similar to a wave of water caused by a fast-moving ship. The origin of this shock wave is thought to be a jet outflow from the multiple star system V380 Orionis off the lower left of the frame....

Explanation: Yes, but can your comet tail do this? No, and what you are seeing is not the tail of a comet. The picture features a cleverly overlayed time-lapse sequence of a group of satellites orbiting Earth together in June. Specifically, these are Starlink communications satellites in low Earth orbit reflecting back sunlight before sunrise to Inner Mongolia, China. Although the satellites appear to the human eye as points, the 20-second-long camera exposures caused them to appear as short streaks. Currently there are over 9000 Starlinks in orbit, with more being launched nearly every week. Other satellite constellations are also...

Explanation: This is the mess that is left when a star explodes. The Crab Nebula, the result of a supernova seen in 1054 AD, is filled with mysterious filaments. The filaments are not only tremendously complex but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The featured image was taken by an amateur astronomer in Leesburg, Florida, USA over three nights last month. It was captured in three primary colors but with extra detail provided by specific emission by hydrogen gas. The Crab Nebula spans about 10...

Explanation: Jewels don't shine this bright -- only stars do. And almost every spot in this jewel-box of an image from the Hubble Space Telescope is a star. Now, some stars are more red than our Sun, and some more blue -- but all of them are much farther away. Although it takes light about 8 minutes to reach Earth from the Sun, NGC 1898 is so far away that it takes light about 160,000 years to get here. This huge ball of stars, NGC 1898, is called a globular cluster and resides in the central bar of the Large...

Explanation: Awkward and angular looking, Apollo 17's lunar module Challenger was designed for flight in the near vacuum of space. Digitally enhanced and reprocessed, this picture taken from Apollo 17's command module America shows Challenger's ascent stage in lunar orbit. Small reaction control thrusters are at the sides of the moonship with the bell of the ascent rocket engine underneath. The hatch that allowed access to the lunar surface is seen at the front, with a round radar antenna at the top. Mission commander Gene Cernan is clearly visible through the triangular window. This spaceship performed gracefully, landing on the...

Explanation: Attention grabbing interstellar visitor 3I/ATLAS made its not-so-close flyby of our fair planet on December 19 at a distance of 1.8 astronomical units. That's about 900 light-seconds. This deep exposure captures the comet from another star system as it gently swept across a faint background of stars in the constellation Leo about 4 days earlier. Though faint, colors emphasized in the image data show off the comet's yellowish dust tail and bluish ion tail along with a greenish tinged coma. And even as it is scrutinized by arrays of telescopes and spacecraft from planet Earth, 3I/ATLAS is headed out...

Explanation: What was so super about Wednesday's supermoon? Last week, a full moon occurred that appeared slightly larger and brighter than usual. The reason is that the Moon's fully illuminated phase occurred within a short time from perigee - when the Moon was its closest to the Earth in its elliptical orbit. Although the precise conditions that define a supermoon vary, last Wednesday's supermoon was surely the closest, largest, and brightest full moon this year. One reason supermoons are popular is because they are so easy to see -- just go outside at sunset and watch an impressive full moon...

Explanation: A star forming region cataloged as NGC 2264, this beautiful but complex arrangement of interstellar gas and dust is about 2,700 light-years distant in the faint but fanciful constellation Monoceros, the Unicorn. Seen toward the celestial equator and near the plane of our Milky Way galaxy, the seasonal skyscape mixes reddish emission nebulae excited by energetic light from newborn stars with dark interstellar dust clouds. Where the otherwise obscuring dust clouds lie close to the hot, young stars, they also reflect starlight, forming blue reflection nebulae. In fact, bright variable star S Monocerotis is immersed in a blue-tinted haze...

Explanation: Does the road to our galaxy's center go through Monument Valley? It doesn't have to, but if your road does -- take a picture. In this case, the road is US Route 163 and iconic buttes on the Navajo National Reservation populate the horizon. The band of Milky Way Galaxy stretches down from the sky and appears to be a continuation of the road on Earth. Filaments of dust darken the Milky Way, in contrast to billions of bright stars and several colorful glowing gas clouds including the Lagoon and Trifid nebulas. The featured picture is a composite of...

Explanation: What is big, bright, and beautiful, can wear a cape made of clouds, and is at the closest point in its elliptical orbit around planet Earth? A full moon at perigee of course, captured here near moonset in predawn skies on November 5 from Kayseri, Turkiye. Full moons that happen at (or very near) perigee, and so are slightly larger and brighter than full moons on average, have become popularly known as supermoons. In fact, this full moon at perigee is the closest and brightest of the three supermoons of 2025. Rising as the Sun sets, this full moon...

Explanation: What's happening in the sky? Lightning. The most commonly seen type of lightning involves flashes of bright white light between clouds. Over the past 50 years, though, other types of upper-atmospheric lightning have been confirmed, including tentacled red sprites and ringed ELVES. Although both last only a small fraction of a second, sprites are brighter and easier to photograph than their more common electrical-discharge cousins. ELVES are rapidly expanding rings that are thought to be created when an electromagnetic pulse shoots upward from charged clouds and impacts the ionosphere, causing nitrogen molecules to glow. Capturing either form of lightning...

Explanation: Yesterday the Sun reached its southernmost point in planet Earth's sky. Called a solstice, many cultures mark yesterday's date as a change of seasons -- from autumn to winter in Earth's Northern Hemisphere and from spring to summer in Earth's Southern Hemisphere. The featured image was taken just before the longest night of the 2025 northern year at Stonehenge in United Kingdom. There, through stones precisely placed 4,500 years ago, a 4.5 billion year old large glowing orb is seen setting. Even given the precession of the Earth's rotational axis over the millennia, the Sun continues to set over...