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Explanation: At the core of the Crab Nebula lies a city-sized, magnetized neutron star spinning 30 times a second. Known as the Crab Pulsar, it is the bright spot in the center of the gaseous swirl at the nebula's core. About twelve light-years across, the spectacular picture frames the glowing gas, cavities and swirling filaments near the Crab Nebula's center. The featured picture combines visible light from the Hubble Space Telescope in purple, X-ray light from the Chandra X-ray Observatory in blue, and infrared light from the Spitzer Space Telescope in red. Like a cosmic dynamo, the Crab pulsar powers...

Explanation: How big is planet Earth's Moon? Compared to other moons of the Solar System, it's number 5 on the largest to smallest ranked list, following Jupiter's moon Ganymede, Saturn's moon Titan, and Jovian moons Callisto and Io. Continuing the list, the Moon comes before Jupiter's Europa and Neptune's Triton. It's also larger than dwarf planets Pluto and Eris. With a diameter of 3,475 kilometers the Moon is about 1/4 the size of Earth though, and that does make it the largest moon when compared to the size of its parent Solar System planet. Of course in this serene, twilight...

After 50 years of secrecy, scientists have finally opened Apollo 17’s Moon samples. The Apollo 17 mission, NASA’s final crewed expedition to the Moon in December 1972, returned with valuable lunar samples, including material from the “Light Mantle,” a bright and unusual deposit at the base of the South Massif in the Taurus-Littrow Valley. Though collected over 50 years ago, these samples have only recently been reopened for detailed analysis as part of the Apollo Next Generation Sample Analysis (ANGSA) Program. This initiative utilizes modern technologies to explore lunar mysteries in preparation for future missions, such as NASA’s Artemis program,...

Explanation: This colorful telescopic view towards the musical northern constellation Lyra reveals the faint outer halos and brighter central ring-shaped region of M57, popularly known as the Ring Nebula. To modern astronomers M57 is a well-known planetary nebula. With a central ring about one light-year across, M57 is definitely not a planet though, but the gaseous shroud of one of the Milky Way's dying sun-like stars. Roughly the same apparent size as M57, the fainter and more often overlooked barred spiral galaxy at the left is IC 1296. In fact, over 100 years ago IC 1296 would have been known...

Looking inside the plasma jet cone of the blazar PKS 1424+240 with a radio telescope of the Very Long Baseline Array (VLBA). Credit: NSF/AUI/NRAO/B. Saxton/Y.Y. Kovalev et al. ==================================================================================== A cosmic jet aimed at Earth reveals how blazars hurl particles to extreme energies, solving a long-standing mystery. Key Points * A glimpse into a galaxy’s core: Astronomers have captured a detailed image of the birthplace of a powerful cosmic jet. With its artificial colors, the view strikingly resembles the legendary “Eye of Sauron.” * The neutrino puzzle: PKS 1424+240 stands out as the brightest known source of neutrinos of its...

NASA reveals a breathtaking photo of Earth and Moon taken from deep space. Credit: NASA/JPL-Caltech/ASU | The Daily Galaxy --Great Discoveries Channel From nearly 290 million kilometers away, NASA’s Psyche spacecraft turned its gaze homeward and captured an arresting glimpse of Earth and the Moon, now just distant specks of light nestled among the stars of the Aries constellation. According to NASA, this deep-space photo opportunity came as part of a scheduled instrument calibration while the spacecraft continues its cruise toward the asteroid Psyche. Testing Cameras With Familiar Cosmic Landmarks The image, taken on July 20 and 23, was created...

Explanation: In this predawn skyscape recorded during the early morning hours of August 13, mostly Perseid meteors are raining down on planet Earth. You can easily identify the Perseid meteor streaks. They're the ones with trails that seem to converge on the annual meteor shower's radiant, a spot in the heroic constellation Perseus, located off the top of the frame. That's the direction in Earth's sky that looks along the orbit of this meteor shower's parent, periodic Comet Swift-Tuttle. Of course the scene is a composite, a combination of about 500 digital exposures to capture meteors registered with a single...

Explanation: What are those curved arcs in the sky? Meteors -- specifically, meteors from this year's Perseid meteor shower. Over the past few weeks, after the sky darkened, many images of Perseid meteors were captured separately and merged into a single frame, taken earlier. Although the meteors all traveled on straight paths, these paths appear slightly curved by the wide-angle lens of the capturing camera. The meteor streaks can all be traced back to a single point on the sky called the radiant, here just off the top of the frame in the constellation of Perseus. The same camera took...

07/01/2025 61.0 km/s =136,560.54 mph 07/04/2025. 61.4 km/s = 137,385.81 mph | Perihelion: 29 Oct 2025 11:29 UTC [-117d 6h 35m 35s] 07/10/2025 61.5 km/s = 137,607.07 mph | Perihelion: 29 Oct 2025 11:29 UTC [-111d 9h 14m 49s] 07/31/2025. 62.2 km/s =139,172.08 mph | Perihelion: 29 Oct 2025 11:29 UTC [-89d 16h 35m 51s] 08/03/2025 . 62.3 km/s = 139,361.08 mph. | 08/05/2025 . 62.4 km/s = 139,582.44 mph | 08/15/2025 . 62.9 km/s = 140,569.70 mph | Perihelion: 29 Oct 2025 11:29 UTC [-74d 20h 25m 14s] 08/16/2025 . 63.0 km/s = 140,790.96 mph | 08/19/2025. 63.1 km/s...

Interstellar object 3I/ATLAS — which is zooming through our inner solar system — appears to be emitting its own light, according to Harvard astrophysicist Avi Loeb. The observation by Loeb, if verified, would contradict NASA’s classification of the Manhattan-sized object as a comet, the scientist argues in a new blog post. Loeb and a colleague analyzed photos released by NASA of the object in determining that the source of its glow is likely not from the sun. The astrophysicist wrote the “brightness profile around 3I/ATLAS implies that the nucleus dominates the observed light.” “The simplest interpretation is that the nucleus...

Across the globe, technology that is designed to generate solar energy could potentially be employed for yet another planet-saving enterprise: Asteroid detection. One scientist at Sandia National Labs has started to get the ball rolling on a theory using a large-scale mirror, and a bit of ingenuity and hope. Sitting just south of Albuquerque is a field of more than 200 large-scale mirrors. These heliostats focus the immense power of the sun on to a 200-foot tower, collecting as much as a million watts of power during the day, but at night, they don’t have a job — they’re just...

Explanation: Over 500,000 light years across, NGC 6872 (bottom left) is a truly enormous barred spiral galaxy. At least 5 times the size of our own large Milky Way, NGC 6872 is the largest known spiral galaxy. About 200 million light-years distant toward the southern constellation Pavo, the Peacock, the appearance of this giant galaxy's stretched out spiral arms suggest the wings of a giant bird. So its popular moniker is the Condor galaxy. Lined with massive young, bluish star clusters and star-forming regions, the extended and distorted spiral arms are due to NGC 6872's past gravitational interactions with the...

The Webb Space Telescope has spotted a new tiny moon orbiting Uranus. The new member of the lunar gang, announced Tuesday by NASA, appears to be just six miles (10 kilometers) wide. It was spotted by the telescope’s near-infrared camera during observations in February. Scientists think it hid for so long — even eluding the Voyager 2 spacecraft during its flyby about 40 years ago — because of its faintness and small size. Uranus has 28 known moons that are named after characters from Shakespeare and Alexander Pope. About half are smaller and orbit the planet at closer range. This...

Artist representation of CAPERS-LRD-z9, home to the earliest confirmed black hole. The supermassive black hole at its center is believed to be surrounded by a thick cloud of gas, giving the galaxy a distinctive red color. Credit: Erik Zumalt, The University of Texas at Austin ================================================================== Astronomers have discovered the most distant confirmed black hole, hidden inside a rare galaxy known as a “Little Red Dot.” Its enormous size and early existence challenge current theories about how galaxies and black holes formed in the young universe. A global team of astronomers, led by The University of Texas at Austin’s Cosmic...

By splitting a single photon, scientists confirmed that angular momentum is always conserved — a billion-to-one experiment that reinforces the foundations of quantum physics. Credit: SciTechDaily.com ===================================================================== Physicists have, for the first time, shown that even a single photon obeys one of nature’s strictest rules: conservation of angular momentum. Achieved only once in a billion attempts, this needle-in-a-haystack success not only proves a cornerstone law of physics at the smallest scale but also opens a pathway to advanced quantum technologies, from entangled states to secure communication. Quantum-Level Confirmation of Angular Momentum Conservation Researchers at Tampere University, working with colleagues in...

Explanation: This galaxy is not only pretty -- it's useful. A gorgeous spiral some 100 million light-years distant, NGC 1309 lies on the banks of the constellation of the River (Eridanus). NGC 1309 spans about 30,000 light-years, making it about one third the size of our larger Milky Way galaxy. Bluish clusters of young stars and dust lanes are seen to trace out NGC 1309's spiral arms as they wind around an older yellowish star population at its core. Not just another pretty face-on spiral galaxy, observations of NGC 1309's two recent supernovas and multiple Cepheid variable stars contribute to...

A geomagnetic storm promises to light up the sky across 15 U.S. states tonight—here’s where to go and how to catch the Northern Lights in all their glory. Tonight, a geomagnetic storm is expected to bring the awe-inspiring Northern Lights to parts of the United States, with the National Oceanic and Atmospheric Administration (NOAA) predicting active aurora displays across 15 states. The event is the latest in a series of heightened solar activities, thanks to the sun being in its “solar maximum,” a period of intense solar activity that leads to more frequent and vivid aurora displays. This forecast gives...

Humans are one step closer to traveling at faster-than-light speeds. Here’s what you’ll learn when you read this story: * A research paper proposes a fully physically realized model for warp drive. * This builds on an existing model that requires negative energy—an impossibility. * The new model is exciting, but warp speed is still probably decades or centuries away. ============================================================= In a surprising paper, scientists say they’ve nailed down a physical model for a warp drive, which flies in the face of what we’ve long thought about the crazy concept of warp speed travel: that it requires exotic, negative...

Ultraviolet observations suggest that some heavy white dwarf mergers might be masquerading themselves. A white dwarf interacting with a red giant. Is this how this white dwarf formed? We do not know yet. Image credit: NASA, ESA, STScI, Ralf Crawford (STScI) Astronomers report the finding of a unique new object that doesn’t fit with categories that were only established in the last few years. They have observed an ultra-massive white dwarf with an outer layer of hydrogen and helium, 10 billion times thinner than other white dwarfs. This object is believed to be the product of a past merger event....

Explanation: What kind of clouds are these? Although their cause is presently unknown, such unusual atmospheric structures, as menacing as they might seem, do not appear to be harbingers of meteorological doom. Formally recognized as a distinct cloud type only last year, asperitas clouds can be stunning in appearance, unusual in occurrence, and are relatively unstudied. Whereas most low cloud decks are flat bottomed, asperitas clouds appear to have significant vertical structure underneath. Speculation therefore holds that asperitas clouds might be related to lenticular clouds that form near mountains, or mammatus clouds associated with thunderstorms, or perhaps a foehn --...