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Explanation: This sight was worth getting out of bed early. Just over four years ago, Comet C/2020 F3 (NEOWISE) rose before dawn to the delight of northern sky enthusiasts awake that early. Up before sunrise on July 8th, the featured photographer was able to capture in dramatic fashion one of the few comets visible to the unaided eye this century, an inner-Solar System intruder that has become known as the Great Comet of 2020. The resulting video detailed Comet NEOWISE from Italy rising over the Adriatic Sea. The featured time-lapse video combines over 240 images taken over 30 minutes. The...

[Note: Catching up for yesterday] Explanation: Bright sunlight glints as long dark shadows mark this image of the surface of the Moon. It was taken on July 20, 1969, by Apollo 11 astronaut Neil Armstrong, the first to walk on the lunar surface. Pictured is the mission's lunar module, the Eagle, and spacesuited lunar module pilot Buzz Aldrin. Aldrin is unfurling a long sheet of foil also known as the Solar Wind Composition Experiment. Exposed facing the Sun, the foil trapped particles streaming outward in the solar wind, catching a sample of material from the Sun itself. Along with 22...

Explanation: Beautiful and bright spiral galaxy M83 lies some twelve million light-years away, near the southeastern tip of the very long constellation Hydra. Prominent spiral arms traced by dark dust lanes and blue star clusters lend this galaxy its popular name, the Southern Pinwheel. Still, reddish star forming regions that dot this cosmic pinwheel's spiral arms have suggested another nickname, the Thousand-Ruby Galaxy. A mere 40,000 light-years across, smaller than the Milky Way, M83 is a member of a group of galaxies that includes active galaxy Centaurus A. In fact, the core of M83 itself is bright at x-ray energies,...

Explanation: What does this image look like to you? Many see a giraffe facing right, with neck stretched high and long legs mid-stride (but some may see a squirrel instead). The featured image shows LDN 1295, also called the Giraffe Nebula, in the constellation of the mythical queen of Aethiopia (Cassiopeia). It is an object in the Lynds Catalogue of Dark Nebulas, compiled in 1962 by American astronomer Beverly Lynds, a pioneer for women in astronomy and astrophysics. Dark nebulas are interstellar clouds of dust and gas that block the visible light of the stars behind them. These nebulas are...

Explanation: Is this star winking at us? The central object in today’s animation is not one but two stars. XZ Andromedae, indicated by the bold lines, is an Algol-type eclipsing binary with a nearly edge-on orbit from Earth’s perspective. The bottom light curve shows the amount of light from the system dim and brighten as the cooler star eclipses its hotter, brighter companion. Analysis of several XZ Andromedae light curves indicates there may be two other stars orbiting the system. This particular light curve was created with Citizen Astronomy, an open-source software for differential photometry. The software takes the difference...

Explanation: Why are Saturn’s poles geometric? Saturn’s North Pole has been known to be surrounded by a hexagonal (6 sides) cloud since discovery in 1987 in data taken by NASA’s Voyager spacecrafts, which quickly flew past the ringed world in the early 1980s. Now, recent observations of Saturn by the Hubble Space Telescope reveal a slightly different geometric cloud pattern around the South Pole: a decagon (10 sides). The geometric boundaries are possibly caused by waves when the fast-moving gas away from the poles interacts with slower-moving gas closer to the poles. In the featured image composite by the Hubble...

Explanation: The Pelican Nebula is slowly being transformed. IC 5070 (an official designation) is divided from the larger North America Nebula by a molecular cloud filled with dark dust. The deep featured picture from Utah, USA incorporates 25 hours of exposure and brings out great details of this filamentary dust. The Pelican Nebula receives much study because it is a particularly active mix of star formation and evolving gas clouds. The light from young energetic stars is slowly transforming the cold gas to hot gas, with the advancing boundary between the two, known as an ionization front, visible in bright...

Explanation: Pluto is more colorful than we can see. Color data and high-resolution images of our Solar System's most famous dwarf planet, taken by the robotic New Horizons spacecraft during its flyby in 2015 July, have been digitally combined to give an enhanced-color view of this ancient world sporting an unexpectedly young surface. The featured enhanced color image is not only esthetically pretty but scientifically useful, making surface regions of differing chemical composition visually distinct. For example, the light-colored heart-shaped Tombaugh Regio on the lower right is clearly shown here to be divisible into two regions that are geologically different,...

Explanation: Chasing the shadow of a New Moon, NASA’s WB-57F high altitude research aircraft took to the skies off the coast of Iceland on August 12 to observe a total solar eclipse. At 50,000 feet the aircraft was piloted along the precisely determined path of totality to maximize its time in the Moon’s shadow. A suite of high-resolution cameras on board was able to record eclipse data from above the clouds, dust, and atmospheric water vapor that interfere with observations made closer to the ground. This view from the cockpit, taken from an inflight video, captures the solar corona emerging...

Explanation: Nā ʻUhane Māhoe Huki Pū i ke Ola, is the Hawaiian name given to this image of a pair of spiral galaxies locked in a mutual gravitational embrace. Some 200 million light-years distant toward the high flying constellation Pegasus their spectacular, galactic scale merger is captured in sharp detail in the image from the 8.1 meter Gemini North telescope on Maunakea, Hawai‘i. The galaxy pair, known as NGC 7253 and Arp 278, was chosen as a target, researched, and given a Hawaiian name by high school students in the joint Gemini Observatory and University of Hawaiʻi Project Hōkūlani internship...

Explanation: How do animals react to a total solar eclipse? The featured image shows a stork roosting on her nest in Poland at a partial phase of the recent total solar eclipse. If you are lucky enough to experience a total eclipse somewhere quiet and close to nature, you may be able to notice unusual daytime animal behaviors. During totality, you may hear nighttime sounds like crickets and frogs and see fireflies. In the dark, most birds are quiet. Thinking that it is time to go to bed, ducks and other waterfowl prepare to sleep on one leg, with their...

Explanation: Pretend you have never heard of a solar eclipse. The Sun’s behavior has been predictable your whole life. One day, you witness the sky transform as it does in today’s spliced image spanning two hours of the August 12, 2026 solar eclipse. The Sun disappears, leaving behind a bright, empty ring. What would you think had happened? Humans have interpreted eclipses in countless ways throughout history, embedding beliefs about connection, rebirth, or danger into culture. “Eclipse” comes from the Greek word “ékleipsis” meaning “abandonment”. In ancient Greece, the solar eclipse marked the anger of the gods and the Sun...

Explanation: Did you need to be on the right side of this airplane to see this eclipse? No. Lunar eclipses are routinely seen from the half of the Earth facing the Moon when the eclipse occurs, making them some of the most commonly witnessed astronomical events. You don't even need any special equipment to see one -- just your unaided eyes. Lunar eclipses are also some of the most photographed astronomical events because, unlike with a solar eclipse, your eyes and camera do not have to look toward the bright Sun. However, considering the featured image taken last week from...

Explanation: A new telescope has been launched into space to study the universe. The Nancy Grace Roman Space Telescope (RST) has the same size main mirror as the Hubble Space Telescope (HST) but sees 100 times more sky during each snapshot. This is possible because when compared to HST, RST's main mirror is more curved, its secondary mirror is closer, and its main camera is larger. The result is that RST can inspect more of the sky more quickly, likely allowing, among other capabilities, the discovery of many more supernovas which tell us more about the expansion rate and composition...

Explanation: If not the most grand, then this spiral galaxy is at least one of the most photogenic. An island universe of about 100 billion stars, 32 million light-years away toward the constellation Pisces, M74 presents a gorgeous face-on view. Classified as an Sc galaxy, the grand design of M74's graceful spiral arms are traced by bright blue star clusters and dark cosmic dust lanes. Constructed from archival images, this sharp composite is from the Hubble Space Telescope. Spanning about 30,000 light-years across the face of M74, it includes exposures recording emission from hydrogen atoms, highlighting the reddish glow of...

Explanation: Eclipses tend to come in pairs. Twice a year, during an eclipse season that lasts about 34 days, Sun, Moon, and Earth can nearly align. Then the new and full phases of the Moon, separated by just over 14 days, create a solar and a lunar eclipse. But only rarely is the alignment at both new moon and full moon during a single eclipse season close enough to produce a pair with both total solar and lunar eclipses. More often, partial eclipses are part of any eclipse season. But, the last eclipse season of 2026 did produce this fortnight-separated...

Explanation: At the latitude of ESO's Paranal Observatory in Chile, about 25 degrees south, Earth's rotation moves the planet's surface eastward at over 1,500 kilometers per hour. And while that's faster than the speed of sound at sea level, the motion is imperceptible. Still, that motion can be revealed in the apparent rotation of the night sky by photographing star trails. This star trail image was composed from a digital stack of 300 consecutive 25-second exposures made with a camera fixed to a tripod to trace the star trail arcs. The graceful arcs are concentric and centered at the south...

Explanation: What a sight to behold, when a night sky became filled with colors that appeared to rain over the Skógafoss waterfall in Iceland. This image was taken in a single 5 second exposure by the photographer in April 2025. Seeing an aurora is on many people's bucket lists. But it is not easy. It requires high solar activity, dark and clear skies, and usually a viewing location at high latitude. That makes the northern lights more easily seen than the corresponding southern lights, simply because there is less landmass in the Southern Hemisphere, especially around the Antarctic Circle. Auroras...

Explanation: Are we looking at the future of our Sun? The James Webb Space Telescope captured today’s composite image of the Lion’s Head Nebula (NGC 2392) with its NIRCam and MIRI instruments. The Lion’s Head Nebula is the remnant of a Sun-like star. This star was unable to sustain the nuclear fusion in its core needed to remain stable. It began to shed layers of gas and dust into space, forming this planetary nebula. A hot stellar core, called a white dwarf, is left behind within the lion’s nose. Do not boop this nose! Intense radiation from the white dwarf...

Explanation: What’s creating this giant hole in space? This is not a black hole — it’s a shadow. It’s Earth’s shadow. Since at least the time of Aristotle, people have noted that Earth's dark shadow on the Moon during a partial lunar eclipse is circular -- although never a whole circle. Using modern digital technology, though, the images of multiple lunar eclipses can be combined to show Earth's complete shadow. The featured image compilation by a perseistent astrophotographer is constructed from 22 years of lunar eclipses. The Moon is not eclipsed every month (moon-th) because the Moon's orbit is slightly...