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Explanation: What are these gigantic blue arcs near the Andromeda Galaxy (M31)? Discovered in 2022 by amateur astronomers, the faint arcs -- dubbed SDSO 1 -- span nearly the same angular size as M31 itself. At first, their origin was a mystery: are they actually near the Andromeda Galaxy, or alternatively near to our Sun? Now, over 550 hours of combined exposure and a collaboration between amateur and professional astronomers has revealed strong evidence for their true nature: SDSO 1 is not intergalactic, but a new class of planetary nebula within our galaxy. Dubbed a Ghost Planetary Nebula (GPN), SDSO...

This artist’s concept depicts NASA’s Europa Clipper as it flies by Mars, using the planet’s gravitational force to alter the spacecraft’s path on its way to the Jupiter system. Credit: NASA/JPL-Caltech ================================================================ During a close Mars flyby, NASA’s Europa Clipper spacecraft tested its radar system, REASON, for the first time in space. The radar’s flawless performance thrilled scientists, as it successfully bounced signals off the Martian surface—proving it’s ready to scan Europa’s ice shell for signs of a hidden ocean. The 60GB of data gathered not only confirmed the hardware’s reliability but also gave researchers an early opportunity to fine-tune...

Explanation: In about a week the Perseid Meteor Shower will reach its maximum. Grains of icy rock will streak across the sky as they evaporate during entry into Earth's atmosphere. These grains were shed from Comet Swift-Tuttle. The Perseids result from the annual crossing of the Earth through Comet Swift-Tuttle's orbit, and are typically the most active meteor shower of the year. Although it is hard to predict the level of activity in any meteor shower, in a clear dark sky an observer might see a meteor a minute. This year's Perseids peak just a few days after full moon,...

Stephen Hawking's chilling warning to humanity may be coming true after a renowned scientist claimed a 'hostile' encounter with alien life could be months away. Hawking, the famous theoretical physicist who died in 2018, warned the world that making contact with alien life could end in disaster for the human race. The late professor believed that actively seeking out extraterrestrials would bring on a deadly invasion, similar to how cultures on Earth have wiped out less advanced civilizations in the past. 'The extraterrestrials would probably be far in advance of us, 'Professor Hawking said in 2004. 'The history of advanced...

Explanation: Taken on July 29 and July 30, a registered and stacked series of exposures creates this dreamlike view of a northern summer night. Multiple firefly flashes streak across the foreground as the luminous Milky Way arcs above the horizon in the Sierra de Órganos national park of central Mexico. The collection of bright streaks aligned across the sky toward the upper left in the timelapse image are Delta Aquariid meteors. Currently active, the annual Delta Aquariid meteor shower shares August nights though, overlapping with the better-known Perseid meteor shower. This year that makes post-midnight, mostly moonless skies in early...

On November 7, 1492, the Ensisheim meteorite was observed to fall in a wheat field outside the walled town of Ensisheim in then Alsace, Further Austria (now France).It was a stony, triangular-shaped meteorite weighing 127 kilograms. The object can still be seen in Ensisheim's Museum, the sixteenth-century Musée de la Régence.Upon impact, the meteorite created a 1-meter (3 ft 3 in) deep hole. Its fall through the Earth's atmosphere was witnessed at a distance of up to 150 kilometers from where it eventually landed.People living in neighboring areas gathered at the location to raise the meteorite from its impact hole....

Astronomers using the NASA/ESA/CSA James Webb Space Telescope have observed the Hubble Ultra Deep Field (HUDF), an area of deep space with nearly 10,000 galaxies in the constellation Fornax. This Webb image shows the Hubble Ultra Deep Field, an area of deep space with thousands of galaxies in various shapes and sizes on a black background. Image credit: NASA / ESA / CSA / Webb / G. Östlin / P. G. Perez-Gonzalez / J. Melinder / JADES Collaboration / M. Zamani, ESA & Webb. ================================================================================= The original HUDF images were pioneering deep-field observations with Hubble published in 2004. They probed...

Explanation: A small, dark, nebula looks isolated near the center of this telescopic close-up. The wedge-shaped cosmic cloudlet lies within a relatively crowded region of space though. About 7,000 light-years distant and filled with glowing gas and an embedded cluster of young stars, the region is known as M16 or the Eagle Nebula. Hubble's iconic images of the Eagle Nebula include the famous star-forming Pillars of Creation, towering structures of interstellar gas and dust 4 to 5 light-years long. But this small dark nebula, known to some as a Bok globule, is a fraction of a light-year across. The Bok...

Astronomers at MIT, Columbia University, and elsewhere have used NASA’s James Webb Space Telescope to peer through the dust of nearby galaxies and into the aftermath of a black hole’s stellar feast. Credit: NRAO/AUI/NSF/NASA Unlike active galaxies that endlessly devour nearby matter, these black holes remain in slumber, stirring only momentarily to consume an unlucky passing star. Astronomers from MIT, Columbia University, and other institutions have used NASA’s James Webb Space Telescope (JWST) to look through thick layers of dust in nearby galaxies and examine the aftermath of black holes consuming stars. According to a new study published on July...

An enormous, 515-mile-long flash of lightning that crossed at least three states has been named the longest in recorded history in the world. The 2017 “megaflash” stretched from eastern Texas to near Kansas City — a distance that would take at least eight hours by car or 90 minutes by commercial plane, according to the World Meteorological Organization. In comparison, the average bolt of lightning usually measures less than 10 miles, according to the National Weather Service.

Explanation: A long time ago in a galaxy 50 million light-years away, a star exploded. Light from that supernova was first detected by telescopes on planet Earth on July 14th though, and the extragalactic transient is now known to astronomers as supernova 2025rbs. Presently the brightest supernova in planet Earth's sky, 2025rbs is a Type Ia supernova, likely caused by the thermonuclear detonation of a white dwarf star that accreted material from a companion in a binary star system. Type Ia supernovae are used as standard candles to establish the distance scale of the universe. The host galaxy of 2025rbs...

Explanation: Our Sun frequently erupts in loops. Hot solar plasma jumps off the Sun's surface into prominences, with the most common type of prominence being a simple loop. The loop shape originates from the Sun's magnetic field, which is traced by spiraling electrons and protons. Many loops into the Sun's lower corona are large enough to envelop the Earth and are stable enough to last days. They commonly occur near active regions that also include dark sunspots. The featured panel shows four loops, each of which was captured near the Sun's edge during 2024 and 2025. The images were taken...

Scientists have long grappled with a fundamental question: what exactly is light?Is it a wave, flowing like ripples across water, or is it made up of tiny particles, like miniature paintballs zipping through space?This fundamental question was at the heart of the double-slit experiment, demonstrating light's dual nature.Just recently, physicists at MIT conducted an experiment using incredible atomic precision.Interestingly, it has definitively resolved a long-standing debate between quantum giants Albert Einstein and Niels Bohr about the elusive nature of light...Einstein believed he could devise an experiment to observe light's particle path and wave interference simultaneously.Bohr, leveraging the uncertainty principle, argued...

Explanation: Is the Helix Nebula looking at you? No, not in any biological sense, but it does look quite like an eye. The Helix Nebula is so named because it also appears that you are looking down the axis of a helix. In actuality, it is now understood to have a surprisingly complex geometry, including radial filaments and extended outer loops. The Helix Nebula (aka NGC 7293) is one of brightest and closest examples of a planetary nebula, a gas cloud created at the end of the life of a Sun-like star. The remnant central stellar core, destined to become...

Credit: NSF NOIRLab/Int.Gemini Ob et al. / SWNS | The Daily Galaxy --Great Discoveries Channel ========================================================================= A team of astrophysicists has raised concerns about a recently discovered interstellar object named 3I/ATLAS, claiming it may not be a comet at all—but potentially a technological artifact of alien origin. Detected on July 1, the object is moving at an extraordinary speed of over 130,000 mph and is expected to reach its closest point to the Sun—its perihelion—later this year, with an arrival window near Earth projected for late November or early December 2025. Strange Features Hint At Alien Design The study, published...

Explanation: Why was this collision so strange? In 2022, to develop Earth-saving technology, NASA deliberately crashed the DART spacecraft into the asteroid moonlet Dimorphos. The hope was that this collision would alter the trajectory of Dimorphos around its parent asteroid Didymos and so demonstrate that similar collisions could, in theory, save the Earth from being hit by (other) hazardous asteroids. But analyses of new results show that the effects of the collision are different than expected -- and we are trying to understand why. Featured here is the time lapse video taken by the ejected LICIACube camera LUKE showing about...

Explanation: Have you ever watched a lightning storm in awe? You're not alone. Details of what causes lightning are still being researched, but it is known that inside some clouds, internal updrafts cause collisions between ice and snow that slowly separate charges between cloud tops and bottoms. The rapid electrical discharges that are lightning soon result. Lightning usually takes a jagged course, rapidly heating a thin column of air to about three times the surface temperature of the Sun. The resulting shock wave starts supersonically and decays into the loud sound known as thunder. On average, around the world, about...

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...

Sunspots, those mysterious dark patches on the Sun's surface, have been observed by astronomers for thousands of years. Yet, despite centuries of study, no one fully understood why these spots could remain stable for such extended periods. New research, however, has finally cracked the case, revealing that the secret lies in a delicate balance between the Sun's magnetic fields and the pressure of its plasma. Sunspots have been documented since at least 27 B.C., with Chinese astronomers recording the phenomenon long before Galileo peered at the Sun through his telescope. Some historical records even suggest that Greek philosopher Anaxagoras might...

Explanation: Meteors from the Kappa Cygnid meteor shower are captured in this time-lapse composite skyscape. The minor meteor shower, with a radiant not far from its eponymous star Kappa Cygni, peaks in mid-August, almost at the same time as the much better-known and better-observed Perseid meteor shower. But, seen to have a peak rate of only about 3 meteors per hour, Kappa Cygnids are vastly outnumbered by the more popular, prolific Perseid shower's meteors that emanate from the heroic constellation Perseus. To capture dozens of Kappa Cygnids, this long term astro-imaging project compiled meteors in exposures selected from over 51...