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Explanation: Only two days after the February New Moon's annular eclipse of the Sun, a slender lunar crescent poses above the western horizon after sunset in this wintry twilight skyscape. Its nightside faintly illuminated by earthshine, the young Moon is joined by three bright planets in the mostly clear, early evening skies above the village of Kirazli, Turkiye. Inner planet Venus appears closest to the horizon. Near the beginning of its 2026 performance as planet Earth's evening star, brilliant Venus is seen through the warm sunset glare near picture center. Straight above Venus, innermost planet Mercury is easy to spot...

Explanation: "A ghost in the Milky Way…” says Christian Bertincourt, the astrophotographer behind this striking image of Barnard 93 (B93). The 93rd entry in Barnard’s Catalogue of Dark Nebulae, B93 lies within the Small Sagittarius Star Cloud (Messier 24), where its darkness stands in stark contrast to bright stars and gas in the background. In some ways, B93 is really like a ghost, because it contains gas and dust that was dispersed by the deaths of stars, like supernovas. B93 appears as a dark void not because it is empty, but because its dust blocks the light emitted by more...

Explanation: Grand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small, irregular galaxies form stars too. In fact, dwarf galaxy IC 2574 shows clear evidence of intense star forming activity in its telltale reddish regions of glowing hydrogen gas. Just as in spiral galaxies, the turbulent star-forming regions in IC 2574 are churned by stellar winds and supernova explosions spewing material into the galaxy's interstellar medium and triggering further star formation. A mere 12 million light-years distant, IC 2574 is part of the M81 group of...

Explanation: Cradled in red-glowing hydrogen gas, stars are being born in Orion. These stellar nurseries lie at the edge of the giant Orion molecular cloud complex, some 1,500 light-years away. This detailed view spans about 12 degrees across the center of the well-known constellation, with the Great Orion Nebula, the closest large star-forming region, visible toward the lower right. The deep mosaic also includes, near the top center, the Flame Nebula and the Horsehead Nebula. Image data acquired with a hydrogen-alpha filter adds other remarkable features to this wide-angle cosmic vista: pervasive tendrils of energized atomic hydrogen gas and portions...

Explanation: Some comets are regular guests of our solar neighborhood; others come by only once, never to return. We won’t have another chance to see Comet C/2024 E1 (Wierzchoś), which is currently making its way through the inner Solar System. The hyperbolic orbit of this comet indicates that it will likely become an interstellar traveler. Comet Wierzchoś is today near its closest approach to the Earth, passing roughly the same distance from the Earth as is the Sun. The featured 30-minute exposure was taken last week in Chile and shows a 5-degree long ion tail as well as three shorter...

Explanation: How is RXJ0528+2838 creating such shock waves? A recently discovered white dwarf star, the farther left of the two largest white spots, RXJ0528+2838, was found 730 light-years away from Earth. Most stars, when done fusing nuclei in their cores for energy, become red giant stars, the cores of which live on as faint dense white dwarfs that slowly cool down for the rest of time. White dwarfs are so dense that the only thing that stops them from collapsing further is quantum mechanics. In about 5 billion years, our Sun will become a white dwarf, too. The featured image,...

Explanation: What would it be like to fly free in space? About 100 meters from the cargo bay of a space shuttle, Bruce McCandless II was living the dream -- floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured, was floating free in space. During Space Shuttle mission 41-B in 1984, McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "untethered space walk". The MMU worked by shooting jets of nitrogen and was used to help deploy and retrieve satellites. With a mass over 140...

Explanation: Roses are red, nebulas are too, and this Valentine's gift is a stunning view! Pictured is a loving look at the Rosette Nebula (NGC 2237): a cosmic bloom of bright young stars sitting atop a stem of glowing hot gas. The rose’s blue-white speckles are among the most luminous stars in the galaxy, with some burning millions of times brighter than the Sun. Their stellar winds sculpt the famed rose shape by pushing gas and dust away from the center. Though only a few million years old, these massive stars are already nearing the end of their lives, while...

Explanation: Dwarf galaxies NGC 147 (left) and NGC 185 stand side by side in this deep telescopic portrait. The two are not-often-imaged satellite galaxies of M31, the great spiral Andromeda Galaxy, some 2.5 million light-years away. Their separation on the sky, less than one degree across a pretty field of view toward the constellation Cassiopeia, translates to only about 35 thousand light-years at Andromeda's distance, but Andromeda itself is found well outside this frame. Brighter and more famous satellite galaxies of Andromeda, M32 and M110, are seen much closer to the great spiral. NGC 147 and NGC 185 have been...

Explanation: Dark, smooth regions that cover the Moon's familiar face are called by Latin names for oceans and seas. That naming convention is historical, though it may seem a little ironic to denizens of the space age who recognize the Moon as a mostly dry and airless world, and the smooth, dark areas as lava-flooded impact basins. For example, this telescopic lunar vista, looks over the expanse of the northwestern Mare Imbrium, or Sea of Rains and into the Sinus Iridum, the Bay of Rainbows. Ringed by the Jura Mountains (montes), the bay is about 250 kilometers across. Seen after...

Explanation: How many sunspots can you see? The central image shows the many sunspots that occurred in 2025, month by month around the circle, and all together in the grand central image. Each sunspot is magnetically cooled and so appears dark -- and can last from days to months. Although the featured images originated from NASA's Solar Dynamics Observatory, sunspots can be easily seen with a small telescope or binoculars equipped with a solar filter. Very large sunspot groups like recent AR 4366 can even be seen with eclipse glasses. Sunspots are still counted by eye, but the total number...

Explanation: Raise your arms if you see an aurora. With those instructions, two nights went by with, well, clouds -- mostly. On the third night of returning to same peaks, though, the sky not only cleared up but lit up with a spectacular auroral display. Arms went high in the air, patience and experience paid off, and the creative featured image was captured as a composite from three separate exposures. The setting is a summit of the Austnesfjorden (a fjord) close to the town of Svolvear on the Lofoten islands in northern Norway. The year was 2014. This year, our...

Explanation: What is Miranda really like? Visually, old images from NASA's Voyager 2 have been recently combined and remastered to result in the featured image of Uranus's 500-kilometer-wide moon. In the late 1980s, Voyager 2 flew by Uranus, coming close to the cratered, fractured, and unusually grooved moon -- named after a character from Shakespeare’s The Tempest. Scientifically, planetary scientists are using old data and clear images to theorize anew about what shaped Miranda's severe surface features. A leading hypothesis is that Miranda, beneath its icy surface, may have once hosted an expansive liquid water ocean which may be slowly...

Explanation: An unusually active sunspot region is now crossing the Sun. The region, labelled AR 4366, is much larger than the Earth and has produced several powerful solar flares over the past ten days. In the featured image, the region is marked by large and dark sunspots toward the upper right of the Sun's disk. The image captured the Sun over a hill in Zacatecas, Mexico, 5 days ago. AR 4366 has become a candidate for the most active solar region in this entire 11-year solar cycle. Active solar regions are frequently associated with increased auroral activity on the Earth....

Explanation: Peering from the shadows, the Saturn-facing hemisphere of tantalizing inner moon Enceladus poses in this Cassini spacecraft image. North is up in the dramatic scene captured during November 2016 as Cassini's camera was pointed in a nearly sunward direction about 130,000 kilometers from the moon's bright crescent. In fact, the distant world reflects over 90 percent of the sunlight it receives, giving its surface about the same reflectivity as fresh snow. A mere 500 kilometers in diameter, Enceladus is a surprisingly active moon. Data and images collected during Cassini's flybys have revealed water vapor and ice grains spewing from...

Explanation: Massive stars in our Milky Way Galaxy live spectacular lives. Collapsing from vast cosmic clouds, their nuclear furnaces ignite and create heavy elements in their cores. After only a few million years for the most massive stars, the enriched material is blasted back into interstellar space where star formation can begin anew. The expanding debris cloud known as Cassiopeia A is an example of this final phase of the stellar life cycle. Light from the supernova explosion that created this remnant would have been first seen in planet Earth's sky about 350 years ago, although it took that light...

Explanation: Active galaxy NGC 1275 is the central, dominant member of the large and relatively nearby Perseus Cluster of Galaxies. Wild-looking at visible wavelengths, the active galaxy is also a prodigious source of x-rays and radio emission. NGC 1275 accretes matter as entire galaxies fall into it, ultimately feeding a supermassive black hole at the galaxy's core. Narrowband image data used in this sharp telescopic image highlights the resulting galactic debris and filaments of glowing gas, some up to 20,000 light-years long. The filaments persist in NGC 1275, even though the turmoil of galactic collisions should destroy them. What keeps...

Explanation: Most galaxies don't have any rings -- why does this galaxy have three? To begin, a ring that's near NGC 1512's center -- and so hard to see here -- is the nuclear ring which glows brightly with recently formed stars. Next out is a ring of stars and dust appearing both red and blue, called, counter-intuitively, the inner ring. This inner ring connects ends of a diffuse central bar of stars that runs horizontally across the galaxy. Farthest out in this wide field image is a ragged structure that might be considered an outer ring. This outer ring...

Explanation: Oh what a tangled web a planetary nebula can weave. The Red Spider Planetary Nebula shows the complex structure that can result when a normal star ejects its outer gases and becomes a white dwarf star. Officially tagged NGC 6537, this two-lobed symmetric planetary nebula houses one of the hottest white dwarfs ever observed, probably as part of a binary star system. Internal winds flowing out from the central stars, have been measured in excess of 1,000 kilometers per second. These winds expand the nebula, flow along the nebula's walls, and cause waves of hot gas and dust to...

Explanation: What part of Orion is this? Just north of the famous Orion Nebula is a picturesque star forming region in Orion's Sword that contains a lot of intricate dust -- some of which appears blue because it reflects the light of bright embedded stars. The region's popular name is the Running Man Nebula because, looked at from the right, part of the brown dust appears to be running legs. Cataloged as Sharpless 279, the reflection nebula is not only part of the constellation of Orion, but part of the greater Orion molecular cloud complex. Light from the Running Man's...