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Explanation: Could the Little Mermaid turn into stardust instead of seafoam? It would seem so in this beautiful nebula. The featured image shows the Mermaid Nebula, also known as the Betta Fish Nebula, which is part of the G296.5+10.0 Supernova Remnant. The blue color visible here originates from doubly ionized oxygen (OIII), while the deep red is emitted by hydrogen gas. Estimated to be located a few thousand light-years away and about 10,000 years old, this nebula was formed when a massive star exploded as a supernova. It left behind a peculiar pulsar, a young radio-quiet neutron star that spins...

Explanation: What looks as if it is going to swallow the great Pillars of Creation? The Eagle Nebula (M16) is not a bird, a plane, or Superman. M16 is actually a combination of several celestial objects. NGC 6611 is the young star cluster that appears to peak out beneath the Eagle’s “wings”. The ultraviolet light from these stars ionizes the surrounding gas, creating the emission nebula IC 4703. The Stellar Spire is seen reaching towards the Pillars of Creation from the left. Both are structures of cold gas and dust that are optimal for star formation. Some astronomers previously thought...

Explanation: Thor not only has his own day (Thursday), but a helmet in the heavens. Popularly called Thor's Helmet, NGC 2359 is a hat-shaped cosmic cloud with wing-like appendages. Heroically sized even for a Norse god, Thor's Helmet is about 30 light-years across. In fact, the cosmic head-covering is more like an interstellar bubble, blown by a fast wind from the bright, massive star near the bubble's center. Known as a Wolf-Rayet star, the central star is an extremely hot giant thought to be in a brief, pre-supernova stage of evolution. NGC 2359 is located about 15,000 light-years away toward...

Explanation: What happens to a comet as it leaves our inner Solar System? Now, the arrival of a comet into the inner Solar System is typically heralded with great fanfare and high hopes that the comet will become bright and photogenic. But on the way out, the comet's nucleus is less warmed by the Sun, less gas and dust are expelled, the bright coma around the nucleus shrinks and fades, and the tail length drops off. Many comets will then return to the outer Solar System and only return in hundreds or thousands of years. In contrast, some comets --...

Explanation: It was visible around the world. The sunset conjunction of Jupiter (left) and Venus (right) in 2012 was visible almost no matter where you lived on Earth. Anyone on our planet with a clear western horizon at sunset could see them. That year, a creative photographer traveled away from the town lights of Szubin, Poland to photograph a near closest approach of the two planets. The bright planets were then separated by only three degrees and his daughter struck a humorous pose. A faint red sunset still glowed in the background. Jupiter and Venus are together again this week...

Explanation: A darkened and mysterious north polar region known to some as Mordor Macula caps this premier view of Charon, Pluto's largest moon. The high-resolution image was captured by the interplanetary space probe New Horizons near its closest approach to distant Pluto on July 14, 2015. The combined blue, red, and infrared image data was processed to enhance colors and follow variations in Charon's surface properties with a resolution of about 2.9 kilometers (1.8 miles). A stunning image of Charon's Pluto-facing hemisphere, it also features a clear view of an apparently moon-girdling belt of fractures and canyons that seems to...

Explanation: Within our own Milky Way galaxy, two bright, spiky stars stand like sentinels in the foreground of this cosmic snapshot. Far beyond them are the galaxies of the Hydra Cluster. In fact, while the spiky foreground stars are hundreds of light-years distant, the Hydra Cluster galaxies are well over 100 million light-years away. Three large galaxies near the cluster center, two yellow ellipticals (NGC 3311, NGC 3309) and one prominent blue spiral (NGC 3312), are the dominant galaxies, each about 150,000 light-years in diameter. An intriguing overlapping galaxy pair cataloged as NGC 3314 lies above and left of NGC...

Explanation: What is happening inside this unusual nebula? Planetary nebula Tc 1, captured here in exquisite detail by the James Webb Space Telescope, is the celestial site where buckyballs were first identified in 2010. Buckminsterfullerene — as buckyballs are officially called — is a molecule with 60 carbon atoms (C60) arranged in the shape of a soccer ball. The molecule is named for architect Buckminster Fuller because of its resemblance to the geodesic dome he helped popularize. Webb’s new data reveal where the C60 molecules live in this nebula, and the geometry is striking: they populate a thin spherical shell...

Explanation: Over 1000 years ago, Persian astronomer Abd al-Rahman al-Sufi published humanity’s oldest known record of the Andromeda Galaxy in "The Book of Fixed Stars" (Bodleian Library MS. Marsh 144 p. 167). 800 years later, Andromeda became the 31st entry in Charles Messier’s "Catalogue of Nebulae and Star Clusters". From “a small cloud” to “nebula” and now known to be our nearest major galaxy, Andromeda has remained a fundamental astronomical object. Today’s image, taken over 202 hours, shows how far we have come in our ability to observe our neighbor. The diffuse red and blue clouds are mostly foreground ionized...

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...

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...

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...