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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...

Explanation: Comet 220P is unexpectedly bright. Normally, periodic Comet 220P/McNaught is so dim that to see it requires a telescope. Two surprising outbursts this year, however, have made it about 20,000 times brighter than usual, so that it is now visible with binoculars and long-duration camera exposures. As expected, Comet 220P continues to orbit the Sun between Mars and Jupiter with a period of over 5 years. The featured long duration exposure, taken 10 days ago from South Africa, shows the comet's bright green head and short dust tail. Reasons for Comet 220P's impressive outbursts are unknown but could be...

Explanation: What would it look like to approach the grand planet Saturn? One doesn't have to just imagine -- the Cassini spacecraft did just this in 2004, recording thousands of images along the way, and hundreds of thousands more since entering orbit. Some of Cassini's early images have been digitally tweaked, cropped, and compiled into the featured inspiring video which is part of a larger IMAX movie project named In Saturn's Rings. In the concluding sequence, Saturn looms increasingly large on approach as cloudy Titan swoops below. With Saturn whirling around in the background, Cassini is next depicted flying over...

Explanation: Recorded the night of August 12-13, images from four dedicated meteor-monitoring cameras at an astronomical observatory in Czechia were aligned and combined to create this all-night, all-sky view. On that night, the total count came to 1,706 meteors. And since that coincided with the peak activity of the 2026 Perseid Meteor Shower, most are perseids. Their overwhelming numbers make them easy to spot. Quite convincingly, perseid trails all trace back to a single radiant on the sky at the upper right, a region in the annual shower's eponymous constellation Perseus. But meteors belonging to other much less active showers...

Explanation: What does it feel like to zoom around a spinning supermassive black hole? The featured video is an animation showing a time-lapse of 4 years of observations of the star S301 orbiting Sagittarius A*, the 4-million-solar-mass black hole in the center of our Galaxy. S301 was discovered in 2023 with the Very Large Telescope Interferometer of the European Southern Observatory, located in the Atacama Desert in Chile. Astronomers recently found that S301 takes approximately 8.7 years to go around the black hole and reaches speeds of 25,000 km/s. It comes closer to the black hole than any other stars...

Explanation: Like an illustration in a galactic Just So Story, the Elephant's Trunk Nebula winds through the emission region and young star cluster complex IC 1396, in the high and far off constellation of Cepheus. Also known as vdB 142, this cosmic elephant's trunk is over 20 light-years long. The detailed telescopic view features the bright swept-back ridges and pockets of cool interstellar dust and gas that abound in the region. But the dark, tendril-shaped clouds contain the raw material for star formation and hide protostars within. Nearly 3,000 light-years distant, the relatively faint IC 1396 complex covers a large...

Explanation: Whatdunit? What disappeared while crossing a partially eclipsed Sun? Let’s present the evidence. The 24 frames-per-second video was taken in Spain (40°34'30.3"N 1°12'28.8"W) at 20:28 local time on August 12, 2026. The Perseids meteor shower was at its peak during this time. Is this a meteor? Meteor showers trace back to a region of the sky called a radiant point that corresponds to where the Earth is crossing a comet’s path. The object’s path might trace back to the Perseids’ radiant point in the Perseus constellation. The object trails a smaller angle on the sky than the 0.5 degree...

Explanation: This was a good year for the Perseids meteor shower. A key reason was the Moon was absent from lighting up Earth's night sky so that more meteors were visible than usual. Where was the Moon? It was busy visiting the Sun. Near the Perseids peak, the Moon moved directly in front of the Sun and created a total solar eclipse visible from Greenland and Spain. The Perseids occur when the Earth collides with a stream of Sun-orbiting debris cast off by Comet Swift-Tuttle. Perseid meteors, although typically only the size of a sand grain, tend to be fast...

Explanation: This total solar eclipse appeared not only poetically beautiful but scientifically interesting. Usually the solar corona appears white, and to some observers the corona of last week's total solar eclipse did appear this pearly color. But this time, totality observers in Spain saw a corona that appeared unusually golden. For one reason, from Spain, the totality occurred when the setting Sun was near the horizon. That low, sunlight travels through a large amount of air which scatters out blue light. An unusual amount of smoke in the air from nearby forest fires acted as a second filter, further scattering...

Explanation: The Milky Way was not created by an evaporating lake. The colorful pool of water, about 10 meters across, is known as Silex Spring and is located in Yellowstone National Park in Wyoming, USA. Illuminated artificially, the colors are caused by layers of bacteria that grow in the hot spring. Steam rises off the spring, heated by underground magma associated with the Yellowstone Hotspot. Unrelated and far in the distance, the central band of our Milky Way Galaxy arches high overhead, a band lit by billions of stars. The picture features a 16-image panorama taken in 2014. If the...

Explanation: Known for its bright and fast meteors, the annual Perseid Meteor Shower comes to planet Earth's skies from a radiant in the heroic constellation Perseus. The popular northern summer celestial spectacle is created as grains of dust cast off along the orbit of periodic comet 109P/Swift-Tuttle vaporize in Earth's dense atmosphere, tracing brief, but beautiful streaks through the night. Taken near the shower's peak of activity on August 12, this composite image recorded two bright perseid meteors and one meteor's watery reflection from a location near the coastal village of Grisslehamn, Sweden. Almost as bright as Altair, brightest star...

Explanation: On August 12, the Moon's shadow reached out to touch our fair planet. Beginning in the Arctic Ocean, it swept along a narrow track that led the dark lunar umbra across parts of Greenland, Iceland, the Atlantic, Portugal, and northern Spain. And for a moment, denizens of Earth who found themselves with clear skies under the shadow of the Moon could witness a total solar eclipse. After dodging the weather by sea and making a landing along Rype Fjord on the Greenland east coast (at 71.07055N, 27.71252W), this hard-won snapshot was captured at 17:33:26 UTC. That's near the initial...

Explanation: On August 12th, 2026, the Moon totally eclipsed the Sun and cast its shadow across Siberia, Greenland, Iceland, Spain, and Portugal. Today’s image features two total solar eclipses viewed from Zaragoza, Spain, one over the Cathedral-Basilica of Our Lady of the Pillar and the other reflecting in the Ebro River. For a few moments, Spain saw its first major total solar eclipse since 1905. Those witnessing totality may experience a chill in the air, the quieting of birds, the confused chirps of insects, and the shared awe of many. It’s the corona’s time to shine as the Sun’s bright...

Explanation: It looks like a view from the Little Prince's planet. The featured image is a throwback to the 2024 Perseid meteor shower, surrounded in this projection by the Bieszczady Mountains in Poland. Visible in the sky is the arch of the Milky Way, along with several nebulas in red and over a hundred meteors pointing to the radiant. The Perseids are easily visible and quite popular in the Northern Hemisphere summer. (Watching meteor showers in the winter is less convenient for a good reason). This year they are expected to offer an even more dazzling spectacle than usual, because...

Explanation: How many moons does Saturn have? While the total will likely continue to grow, as of June 2026 the ringed gas giant had 293 confirmed moons. That's easily more than any other planet of the Solar System, including ruling gas giant Jupiter with a mere 115 confirmed moons. Most of Saturn's known moons are small, irregular satellites. Many are only few kilometers to a fraction of a kilometer across and grouped in tilted outer orbits. Six of its largest satellites can be seen here, though, in this sharp telescopic Saturnian family portrait taken on August 5. Larger than Earth's...