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Explanation: What does it take to image hundreds of nebulas? Today’s image contains the entire Sharpless Catalog of H II Regions, totaling 313 objects. Zoom in and explore! You may spot fan favorites like the Eagle (Sh2-49), Heart (Sh2-190), and Orion (Sh2-281) Nebulas. Despite its name, this catalog contains more than the glow of ionized hydrogen that makes up H II regions. There are planetary nebulas (the Medusa Nebula, Sh2-274) and supernova remnants (the Spaghetti Nebula, Sh2-240) as well. Astrophotographer Bing Xin traversed the dark skies of Eastern China and Inner Mongolia to catch them all. Narrowband filters that primarily...

Explanation: Have you ever seen the full moon rise? This colorful image was photographed last weekend in Sicily, just outside the town of Nicosia, in Italy. It is a composite photograph that shows the Moon rising as the sky turns darker. Lower clouds are reflecting the colors of antitwilight, while ash and gas from Mount Etna are seen higher in the background. The pink band lower in the sky is called the Belt of Venus. During a full moon, the Moon and the Sun are in opposition in the sky: the moon rises as the sun sets. The lunar phase...

Explanation: Peculiar spiral galaxy Arp 78 is found within the boundaries of the head strong constellation Aries. Some 100 million light-years beyond the stars and nebulae of our Milky Way galaxy, the island universe is an enormous 200,000 light-years across. Also known as NGC 772, it sports a prominent, outer spiral arm in this detailed cosmic portrait. Tracking along sweeping dust lanes and lined with young blue star clusters, Arp 78's overdeveloped spiral arm is pumped-up by galactic-scale gravitational tides. Interactions with its brightest companion galaxy, the more compact NGC 770 seen directly below the larger spiral, are likely responsible....

SpaceX and NASA are targeting Thursday, October 1 for Falcon 9's launch of Dragon's 13th operational human spaceflight mission (Crew-13) to the International Space Station from Space Launch Complex 40 (SLC-40) at Cape Canaveral Space Force Station in Florida. Launch is targeted for 11:10 a.m. ET, with a backup opportunity available on Friday, October 2 at 10:47 a.m. ET. SpaceX's live webcast of this mission will begin about one hour prior to liftoff, which you can watch here and on X @SpaceX. The Dragon spacecraft supporting this mission previously flew the Ax-4, mission to and from the space station. This...

This is not an easy undertaking. ... The SR-71 program was scrapped decades ago. There are few people alive who remember how the engines were designed and built. And yet, it seems NASA is getting the gang back together: ... Mike Relja, a retiree in his late 70s, received an unexpected job offer from NASA about a month ago. The assignment: Help put a former NASA-operated Lockheed SR-71A Blackbird back in the air after a nearly 27-year hiatus. Relja, an ex-U.S. Air Force and NASA test engineer for the SR-71A, could not believe his ears. David Ash, a former U.S....

Explanation: What causes the swirl in the Shrimp Nebula? Its high speed is likely. What is sure is that Sh2-188 is one of the larger planetary nebulas on the night sky, by angular size, spanning about half the diameter of the Moon. Moreover, the white-dwarf core -- leftover from the Sun-like star that shed its outer atmosphere -- is moving unusually fast through interstellar space, creating a bow shock most visible on the upper left that is similar to a boat plowing through water. Although faint, the Shrimp Nebula glows also by compressing and brightening gas on its leading edge....

Explanation: What color is the universe? More precisely, if the entire sky were smeared out, what color would the final mix be? This whimsical question came up when trying to determine what stars are commonplace in nearby galaxies. The answer, depicted here, is a conditionally perceived shade of beige. In computer parlance: #FFF8E7. To determine this, astronomers computationally averaged the light emitted by one of the larger samples of galaxies analyzed: the 200,000 galaxies of the 2dF Galaxy Redshift Survey. The resulting cosmic spectrum has some emission in all parts of the electromagnetic spectrum, but a single perceived composite color....

Explanation: What does the Andromeda galaxy really look like? The featured image shows how our Milky Way Galaxy's closest major galactic neighbor really appears in a long exposure through Earth's busy skies and with a digital camera that introduces normal imperfections. The picture is a stack of 223 images, each a 300 second exposure, taken from a garden observatory in Portugal during 2019. Obvious image deficiencies include bright parallel airplane trails, long and continuous satellite trails, short cosmic ray streaks, and bad pixels. These imperfections were actually not removed with Photoshop specifically, but rather greatly reduced with a series of...

NASA's Artemis III mission is about three months behind schedule, administrator Jared Isaacman says, putting pressure on the agency's plan to launch two moon-landing missions in 2028. In a wide-ranging email to employees on Sunday, Isaacman said Artemis III could launch in the summer of 2027, preserving two opportunities for lunar landings the following year. But that's the "best-case scenario." NASA doesn't plan to put astronauts on the moon during Artemis III. The agency redesigned the mission earlier this year as a crewed flight in Earth orbit, wherein astronauts would rehearse docking the Orion spacecraft with lunar landers built by...

Explanation: On August 15, this perseid meteor streaked through night skies over the Observatorio del Roque de los Muchachos at La Palma, Canary Islands, Spain. The bright and colorful meteor trail was captured next to the central Milky Way, whose dark interstellar dust clouds and luminous starlight reach above the horizon. In the foreground of this tantalizing celestial scene is the 23 meter diameter mirror of the prototype Large-Sized Telescope (LST-1). LST-1 is the first telescope constructed at the northern hemisphere site of the innovative Cherenkov Telescope Array Observatory. With 198 hexagonal mirror segments and a large, high-efficiency, pixelized camera,...

Explanation: Globular star cluster Omega Centauri packs about 10 million stars much older than the Sun into a volume some 150 light-years in diameter. Also known as NGC 5139, at a distance of 15,000 light-years it's the largest and brightest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. Though most star clusters consist of stars with the same age and composition, the enigmatic Omega Cen exhibits the presence of different stellar populations with a spread of ages and chemical abundances. In fact, Omega Cen may be the remnant core of a small...

Explanation: The ghosts of five supernovas haunt this extraordinary image. It was acquired at Oukaïmeden Observatory in Morocco with approximately 200 hours of observations and shows a large patch of the sky, equivalent to the area of one thousand full moons tiled together, in the constellation of Auriga (the Charioteer). From left to right, the five supernova remnants visible across the field are G181.1+9.5, G182.4+4.3, G179.0+2.6, G180.0−1.7 (Sh2-240, the Spaghetti Nebula), and G178.2−4.2. They are highlighted in the annotated image, together with open cluster M37 and the Tadpole Nebula. As each explosion expanded into space, it created a growing shell...

Explanation: A once-in-a-lifetime crater has appeared on the Moon! A comet or asteroid roughly the size of a humpback whale (approximately 10-20 meters, 30-60 feet) crashed into the Moon sometime between April and May of 2024. The Lunar Reconnaissance Orbiter (LRO), with its monthly monitoring of the Moon, captured today’s images of the lunar surface before and after the event. The resulting crater, named after Apollo-era lunar scientist McGetchin, is two soccer fields across. Craters of this size are only expected once every 132 years! Follow up thermal imaging revealed a large cold spot that surrounds the warm crater. Surface...

Explanation: This shot captured an unexpected silhouette. Which is it? It isn't the sunspots, the small dark regions caused by concentrated magnetic fields visible around the Sun's bright disk. Sunspots typically last for weeks and were expected, since these spots were seen previously. It isn’t the International Space Station (ISS), the small dark structure on the middle left. This is because the featured picture was planned with sub-second timing to record the iconic structure passing before the Sun. It is the airplane. Just as this exposure was taking place in June, from Prasek in the Czech Republic, an airplane began...

Explanation: When does a nebula look like a comet? In this crowded starfield covering over two degrees within the high-flying constellation of the Swan (Cygnus), the eye is drawn to the Cocoon Nebula. A compact star forming region, the cosmic Cocoon punctuates a nebula bright in emission and reflection on the lower right, with a long trail of interstellar dust clouds to the left, making the entire complex appear a bit like a comet. Cataloged as IC 5146, the central bright head of the nebula spans about 10 light years, while the dark dusty tail spans nearly 100 light years....

Explanation: If you went outside at the same time every day and took a picture that included the Sun, how would the Sun's position change? A visual answer to that question is an analemma, a composite image taken from the same spot at the same time over the course of a year. The featured analemma was composed from images taken every few days at noon near the village of Callanish in the Outer Hebrides in Scotland, UK. In the foreground are the Callanish Stones, a stone circle built around 2700 BC during humanity's Bronze Age. It is not known if...

Explanation: Also known as the false dawn, a luminous band of zodiacal light is captured in this dark night skyscape. The serene view was recorded just before the beginning of astronomical twilight during September's star party at the remote Hanle Dark Sky Reserve, Ladakh, India, planet Earth. At about 4,500 meters altitude, the dark sky reserve presents a haven for hardy stargazing and astrophotography enthusiasts. While meteors streak through the night, bright planet Jupiter appears immersed in the faint zodiacal glow near the eastern horizon. Follow the zodiacal band toward the zenith to find open star cluster M44 and a...

You're invited.This September 19, observe the Moon with NASA.Each year, observers around the world come together to celebrate Earth's Moon through direct observations, hands-on activities, lunar-themed music, artwork, readings, and more.Join in from wherever you are: Observe the Moon from home, host a virtual or in-person event, or find an event near you.Learn More

Explanation: The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, Messier 33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy. M33 is over 50,000 light-years in diameter, third largest in the Local Group of galaxies after the Andromeda Galaxy (M31), and our own Milky Way. About 3 million light-years from the Milky Way, M33 is itself thought to be a satellite of the Andromeda Galaxy and astronomers in these two galaxies would likely have spectacular views of each other's grand spiral star systems. As for the view from the Milky Way, this sharp telescopic...

Explanation: This treasure chest is full of stars. The featured image was obtained with NASA's James Webb Space Telescope and shows a dust pillar in the Carina Nebula inside our Galaxy, roughly 7500 light-years away. It is formed by interstellar gas and dust, and shaped by powerful stellar winds and radiation form neighboring stars like the nearby Eta Carinae stellar system which is more luminous than 5 million suns. The star formation inside the pillar is excavating its head, creating the open lid of the chest. Astronomers estimate that there are about 70 stars in a compact cluster inside the...