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Explanation: Sometimes the night sky is full of surprises. Take the sky over Lindis Pass, South Island, New Zealand one-night last week. Instead of a typically calm night sky filled with constant stars, a busy and dynamic night sky appeared. Suddenly visible were pervasive red aurora, green picket-fence aurora, a red SAR arc, a STEVE, a meteor, and the Moon. These outshone the center of our Milky Way Galaxy and both of its two satellite galaxies: the LMC and SMC. All of these were captured together on 28 exposures in five minutes, from which this panorama was composed. Auroras lit...

Explanation: How bright and strange will the tails of Comet Tsuchinshan-ATLAS become? The comet has brightened dramatically over the few weeks as it passed its closest to the Sun and, just three days ago, passed its closest to the Earth. C/2023 A3 (Tsuchinshan–ATLAS) became of the brightest comets of the past century over the past few days, but was unfortunately hard to see because it was so nearly superposed on the Sun. As the comet appears to move away from the Sun, it is becoming a remarkable sight -- but may soon begin to fade. The featured animated video shows...

Explanation: Go outside at sunset tonight and see a comet! C/2023 A3 (Tsuchinshan–ATLAS) has become visible in the early evening sky in northern locations to the unaided eye. To see the comet, look west through a sky with a low horizon. If the sky is clear and dark enough, you will not even need binoculars -- the faint tail of the comet should be visible just above the horizon for about an hour. Pictured, Comet Tsuchinshan-ATLAS was captured two nights ago over the Lincoln Memorial monument in Washington, DC, USA. With each passing day at sunset, the comet and its...

Explanation: Did you see last night's aurora? This question was relevant around much of the world a few days ago because a powerful auroral storm became visible unusually far from the Earth's poles. The cause was a giant X-class solar flare on Tuesday that launched energetic electrons and protons into the Solar System, connecting to the Earth via our planet's magnetic field. A red glow of these particles striking oxygen atoms high in Earth's atmosphere pervades the frame, while vertical streaks dance. The featured video shows a one-hour timelapse as seen from Cortina d'Ampezzo over Alps Mountain peaks in northern...

Catching up after the power and internet outage due to Hurricane MiltonExplanation: A gravel country lane gently winds through this colorful rural night skyscape. Captured from Monroe County in southern West Virginia on the evening of October 10, the starry sky above is a familiar sight. Shimmering curtains of aurora borealis or northern lights definitely do not make regular appearances here, though. Surprisingly vivid auroral displays were present on that night at very low latitudes around the globe, far from their usual northern and southern high latitude realms. The extensive auroral activity was evidence of a severe geomagnetic storm triggered...

Catching up from the power and internet outage from Hurricane MiltonExplanation: The second solar eclipse of 2024 began in the Pacific. On October 2nd the Moon's shadow swept from west to east, with an annular eclipse visible along a narrow antumbral shadow path tracking mostly over ocean, making its only major landfall near the southern tip of South America, and then ending in the southern Atlantic. The dramatic total annular eclipse phase is known to some as a ring of fire. Also tracking across islands in the southern Pacific, the Moon's antumbral shadow grazed Easter Island allowing denizens to follow...

Catching up after the power and internet outage due to Hurricane Milton Explanation: Five bright comets are compared in these panels, recorded by a coronograph on board the long-lived, sun-staring SOHO spacecraft. Arranged chronologically all are recognizable by their tails streaming away from the Sun at the center of each field of view, where a direct view of the overwhelmingly bright Sun is blocked by the coronagraph's occulting disk. Each comet was memorable for earthbound skygazers, starting at top left with Comet McNaught, the 21st century's brightest comet (so far). C/2023 A3 Tsuchinshan-ATLAS, approaching its perihelion with the active Sun...

Explanation: What's happening at the center of spiral galaxy M106? A swirling disk of stars and gas, M106's appearance is dominated by blue spiral arms and red dust lanes near the nucleus, as shown in the featured image taken from the Kuwaiti desert. The core of M106 glows brightly in radio waves and X-rays where twin jets have been found running the length of the galaxy. An unusual central glow makes M106 one of the closest examples of the Seyfert class of galaxies, where vast amounts of glowing gas are thought to be falling into a central massive black hole....

Explanation: Can you find the Sun? OK, but can you explain why there’s a big dark spot in the center? The spot is the Moon, and the impressive alignment shown, where the Moon lines up inside the Sun, is called an annular solar eclipse. Such an eclipse occurred just last week and was visible from a thin swath mostly in Earth's southern hemisphere. The featured image was captured from Patagonia, Chile. When the Moon is significantly closer to the Earth and it aligns with the Sun, a total solar eclipse is then visible from parts of the Earth. Annular eclipses...

Explanation: A bright comet is moving into the evening skies. C/2023 A3 (Tsuchinshan–ATLAS) has brightened and even though it is now easily visible to the unaided eye, it is so near to the Sun that it is still difficult to see. Pictured, Comet Tsuchinshan–ATLAS was captured just before sunrise from an Andes Mountain in Peru. Braving cold weather, this unusually high perch gave the astrophotographer such a low eastern horizon that the comet was obvious in the pre-dawn sky. Visible in the featured image is not only an impressively long dust tail extending over many degrees, but an impressively long...

Explanation: Comet McNaught, the Great Comet of 2007, grew a spectacularly long and filamentary tail. The magnificent tail spread across the sky and was visible for several days to Southern Hemisphere observers just after sunset. The amazing ion tail showed its greatest extent on long-duration, wide-angle camera exposures. During some times, just the tail itself was visible just above the horizon for many northern observers as well. Comet C/2006 P1 (McNaught), estimated to have attained a peak brightness of magnitude -5 (minus five), was caught by the comet's discoverer in the featured image just after sunset in January 2007 from...

Explanation: While hunting for comets in the skies above 18th century France, astronomer Charles Messier diligently kept a list of the things encountered during his telescopic expeditions that were definitely not comets. This is number 27 on his now famous not-a-comet list. In fact, 21st century astronomers would identify it as a planetary nebula, but it's not a planet either, even though it may appear round and planet-like in a small telescope. Messier 27 (M27) is an excellent example of a gaseous emission nebula created as a sun-like star runs out of nuclear fuel in its core. The nebula forms...

Explanation: Comet C/2023 A3 (Tsuchinshan–ATLAS) is growing brighter in planet Earth's sky. Fondly known as comet A3, this new visitor to the inner Solar System is traveling from the distant Oort cloud. The comet reached perihelion, its closest approach to the Sun, on September 27 and will reach perigee, its closest to our fair planet, on October 12, by then becoming an evening sky apparition. But comet A3 was an early morning riser on September 30 when this image was made. Its bright coma and already long tail share a pre-dawn skyscape from Praia Grande, Santa Catarina in southern Brazil...

Explanation: The second solar eclipse of 2024 began in the Pacific. On October 2nd the Moon's shadow swept from west to east, with an annular eclipse visible along a narrow antumbral shadow path tracking mostly over ocean, crossing land near the southern tip of South America, and ending in the southern Atlantic. The dramatic total annular eclipse phase is known to some as a ring of fire. Still, a partial eclipse of the Sun was experienced over a wide region. Captured at one of its earliest moments, October's eclipsed Sun is seen just above the clouds near sunrise in this...

Explanation: It is the largest satellite galaxy of our home Milky Way Galaxy. If you live in the south, the Large Magellanic Cloud (LMC) is quite noticeable, spanning about 10 degrees across the night sky, which is 20 times larger than the full moon towards the southern constellation of the dolphinfish (Dorado). Being only about 160,000 light years away, many details of the LMC's structure can be seen, such as its central bar and its single spiral arm. The LMC harbors numerous stellar nurseries where new stars are being born, which appear in pink in the featured image. It is...

Explanation: How far can black hole jets extend? A new record was found just recently with the discovery of a 23-million light-year long jet pair from a black hole active billions of years ago. Dubbed Porphyrion for a mythological Greek giant, the impressive jets were created by a type of black hole that does not usually create long jets -- one that is busy creating radiation from infalling gas. The featured animated video depicts what it might look like to circle around this powerful black hole system. Porphyrion is shown as a fast stream of energetic particles, and the bright...

Explanation: The new comet has passed its closest to the Sun and is now moving closer to the Earth. C/2023 A3 (Tsuchinshan–ATLAS) is currently moving out from inside the orbit of Venus and on track to pass its nearest to the Earth in about two weeks. Comet Tsuchinshan-ATLAS, pronounced "Choo-cheen-shahn At-less,", is near naked-eye visibility and easily picked up by long-exposure cameras. The comet can also now be found by observers in Earth's northern hemisphere as well as the south. The featured image was captured just a few days ago above Zacatecas, Mexico. Because clouds were obscuring much of the...

Explanation: Is this really the famous Pleiades star cluster? Known for its iconic blue stars, the Pleiades is shown here in infrared light where the surrounding dust outshines the stars. Here, three infrared colors have been mapped into visual colors (R=24, G=12, B=4.6 microns). The base images were taken by NASA's orbiting Wide Field Infrared Survey Explorer (WISE) spacecraft. Cataloged as M45 and nicknamed the Seven Sisters, the Pleiades star cluster is by chance situated in a passing dust cloud. The light and winds from the massive Pleiades stars preferentially repel smaller dust particles, causing the dust to become stratified...

Explanation: Shockwaves ripple across the glare as a launch eclipses the setting Sun in this exciting close-up. Captured on September 17, the roaring Falcon 9 rocket carried European Galileo L13 navigation satellites to medium Earth orbit after a lift-off from Cape Canaveral on Florida's space coast. The Falcon 9 booster returned safely to Earth about 8.5 minutes later, notching the 22nd launch and landing for the reusable workhorse launch vehicle. But where did it land? Just Read the Instructions.

Explanation: The twenty galaxies arrayed in these panels are part of an ambitious astronomical survey of tidal stellar streams. Each panel presents a composite view; a deep, inverted image taken from publicly available imaging surveys of a field that surrounds a nearby massive galaxy image. The inverted images reveal faint cosmic structures, star streams hundreds of thousands of light-years across, that result from the gravitational disruption and eventual merger of satellite galaxies in the local universe. Such surveys of mergers and gravitational tidal interactions between massive galaxies and their dwarf satellites are crucial guides for current models of galaxy formation...