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Explanation: The explosion is over, but the consequences continue. About twelve thousand years ago, a relatively normal star in the constellation Vela suddenly exploded, creating a strange point of light briefly visible to humans living near the beginning of recorded history. The outer layers of the star crashed into the interstellar medium, driving a shock wave that is still visible today. The featured image, taken piecemeal over 60 hours from the Khomas Region of Namibia, captures some of that filamentary and gigantic shock in visible light, with details highlighted by hydrogen (red) and oxygen (blue) emissions. As gas flies away...

Explanation: Telescopic views of Saturn and its beautiful rings often make it the star of star parties. But this stunning view of the outer gas gaint planet's rings and night side just isn't possible from telescopes in the vicinity of planet Earth. Peering out from the inner Solar System they can only bring Saturn's day side into view. In fact, this image of Saturn's slender sunlit crescent with the planet's night shadow cast across its broad and complex ring system was captured by the robot spacecraft Cassini. After a seven year long journey from planet Earth, Cassini called Saturn orbit...

Explanation: Newborn stars are forming in the Eagle Nebula. They are gravitationally contracting in pillars of dense gas and dust. The intense radiation of these newly-formed bright stars is causing surrounding material to boil away. This image, taken with the Hubble Space Telescope in near infrared light, allows the viewer to see through much of the thick dust that makes the pillars opaque in visible light. The giant structures are light years in length and dubbed informally the Pillars of Creation. Associated with the open star cluster M16, the Eagle Nebula lies about 6,500 light years away. The Eagle Nebula...

The Sun runs on an 11-year cycle of rising and falling activity, tracked mainly by counting sunspots – the dark patches scattered across its surface. Solar Cycle 25, the current cycle, was forecast as mild, and the sunspot count agreed. But those counts read only the surface. A global network of six telescopes has listened to the Sun’s interior for nearly 40 years, and what it is now telling researchers is not what the surface suggested at all. Listening inside the Sun Scientists have a name for eavesdropping on those sound waves: helioseismology. The waves are trapped inside the Sun,...

The concept of the Einstein-Rosen bridge is often understood as a cosmic shortcut, akin to a tunnel that links distant points in spacetime. While that image makes for compelling science fiction, a new study shows that it does not match the actual physics behind this concept. Recent research suggests that the original bridge theory was not a wormhole but a mathematical feature of how time is structured. This new realization could help solve a persistent problem in physics. The study, led by Professor Enrique Gaztañaga from the University of Portsmouth, along with K. Sravan Kumar and João Marto, was published...

Explanation: What is so micro about tonight's blue micromoon? Just after sunset, a full moon will appear slightly smaller and dimmer than usual. The reason is that the Moon's fully illuminated phase occurs within a short time of apogee - when the Moon is farthest from the Earth in its elliptical orbit. In fact, tonight's micromoon will be the farthest, smallest, and dimmest Moon this year. But tonight's micromoon is notable for yet another reason: it is also a blue moon, meaning that it is the second full moon in the same month (moon-th). Pictured here, a supermoon -- when...

Explanation: A gorgeous spiral galaxy, Messier 104 is famous for its nearly edge-on profile featuring a broad ring of obscuring dust lanes. Seen in silhouette against an extensive central bulge of stars, the swath of cosmic dust lends a broad brimmed hat-like appearance to the galaxy suggesting a more popular moniker, the Sombrero Galaxy. Also known as NGC 4594, the Sombrero galaxy can be seen across the spectrum and is host to a central supermassive black hole. About 50,000 light-years across and 28 million light-years away, M104 is one of the largest galaxies at the southern edge of the Virgo...

xplanation: What do you see in this crystal ball? The featured image shows NGC 1514, known as the Crystal Ball Nebula, observed by the Gemini North telescope on Maunakea, in Hawai'i. NGC 1514 is 1,500 light-years away and was discovered by William Herschel in 1790. This planetary nebula is formed when a star becomes a red giant and ejects its outer gas layers. The ejected shell of gas is heated up by the core of the star to temperatures hotter than the surface of our Sun: that makes the gas shine, creating beautiful images like this one. The slightly asymmetrical...

Explanation: What is a pair of headphones doing in the sky? Today’s image features the Headphone Nebula, also known as PK 164 +31.1 or Jones-Emberson 1. This planetary nebula, the remnant of a dying Sun-like star, faintly occupies an angular region of the Lynx constellation about 1/5th the diameter of the full moon. The red and blue-ish green colors trace hydrogen and oxygen atoms, respectively, that have been excited and ionized by the nebula's central white dwarf. The headphone shape, where two lobes of hydrogen puncture the inner region of oxygen, adds this object to a long list of oddly...

Explanation: The upper galaxy might be more photogenic, but the lower galaxy is more unusual. The galaxy up top is NGC 3660, a spiral galaxy similar to our own Milky Way galaxy in that it has several bright blue spiral arms and a central bar of stars, dust, and gas. Captured by chance in the featured deep and colorful image, surprisingly, is SN 2026cff, a supernova found just to the right of the central bar. Farther in the distance is the bottom galaxy, known informally as Burçin’s galaxy, but formally cataloged as LEDA 1000714. The center of this galaxy appears...

Explanation: What are these strange space globs? Situated in rich star fields and glowing hydrogen gas, these opaque clouds of interstellar dust and gas are so large they might be able to form stars. Their home is known as IC 2944, a bright stellar nursery located about 7,600 light years away toward the constellation of the Centaur (Centaurus). The largest of these dark globules, first spotted by A. D. Thackeray in 1950 using a telescope in South Africa, is likely two separate but overlapping clouds, each more than one light-year wide. Along with other data, the featured Hubble palette image...

"The evidence for water vapor plumes on Europa isn’t as strong as we first understood it,"

Explanation: What's that passing in front of the Sun? It looks like a moon, but it can't be Earth's Moon, because it isn't round. It's the Martian moon Phobos. The featured video was taken from the surface of Mars in 2022 by the Perseverance rover. Phobos, at 11.5 kilometers across, is 150 times smaller than Luna (our moon) in diameter, but also 50 times closer to its parent planet. In fact, Phobos is so close to Mars that it is expected to break up and crash into Mars within the next 50 million years. In the near term, the low...

Explanation: After the Crab Nebula, this giant star cluster is the second entry in 18th century astronomer Charles Messier's famous list of things that are not comets. M2 is one of the largest globular star clusters now known to roam the halo of our Milky Way galaxy. Though Messier originally described it as a nebula without stars, this stunning Hubble image resolves stars across the cluster's central 40 light-years. Its population of stars numbers close to 150,000, concentrated within a total diameter of around 175 light-years. About 55,000 light-years distant toward the constellation Aquarius, this ancient denizen of the Milky...

NASA's Mars Perseverance rover has stumbled across an unusual sight: a stack of rocks on the Martian surface. How did they end up this way? Did Perseverance knock them over? So many questions. What is it? Perseverance, or Percy for short, captured this bizarre image of rocks stacked on Mars on May 13(or Sol 1859, the rover's 1,859th day on the Red Planet). The image was captured with the rover's Mastcam-Z camera — a pair of two cameras located high up on the rover's mast, looking almost like a pair of eyes that the craft sees through. You may have...

Explanation: This cosmic snapshot covers a field of view over twice as wide as the full Moon within the boundaries of the high-flying constellation Cygnus. Made using astronomical narrowband filters, the image highlights the bright edge of a ring-like nebula traced by the glow of ionized hydrogen and oxygen gas. Embedded in the region's expanse of interstellar clouds, the complex, glowing arcs are sections of shells of material swept up by the wind from Wolf-Rayet star WR 134, the brightest star near image center. Distance estimates put WR 134 about 6,000 light-years away, making this telescopic frame over 100 light-years...

OK - I got one yanked a while back - still not perfectly clear on what things will get something you post pulled, but I think the last one had something to do with a title not matching source title?

Credit: CTIO/NOIRLab/DOE/NSF/AURA/J. Pollard Image Processing: D. de Martin & M. Zamani (NSF NOIRLab) =============================================================================== In A Nutshell A 37-member international team produced the most precise direct measurement of the Hubble constant ever recorded, with just 1.1 percent uncertainty. By linking a dozen different cosmic distance measurement methods into a single “Distance Network,” they confirmed the universe is currently expanding at about 73.5 kilometers per second per 3.26 million light-years. That rate conflicts with what the Big Bang’s ancient afterglow predicts by more than seven times the margin of error, a gap that makes a simple measurement mistake increasingly implausible. Resolving...

Explanation: This big beautiful spiral shines in X-ray light. It is about 20 times larger than our Galaxy. It belongs to Abell 2029, a galaxy cluster one billion light-years away. (To see only the galaxies, hover your cursor over the image, or follow this link.) Galaxy clusters are the largest structures in the universe that are supported by gravity. Abell 2029 is formed by thousands of galaxies, surrounded by a huge cloud of hot gas and the equivalent of hundreds of trillions times the mass of the Sun in dark matter. The spiral is made of gas, mostly hydrogen and...

Explanation: A dark wolf lies in gum. No, this isn’t a riddle! Today's image features the Dark Wolf Nebula (Sandqvist–Lindroos 17), a spooky dust cloud embedded within the Gum 55 (RCW 113) Nebula in the Scorpius constellation. While dust is a pest to us, it serves a vital role in creating the necessary conditions for stars to be born. The Dark Wolf absorbs the intense ultraviolet and visible light emitted by young stars in Gum 55 and re-emits it at longer, mainly infrared, wavelengths. This prevents the higher energy light from heating up the gas in the region. When a...