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Artist’s impression of the collision between the early Earth and Theia. Since Theia originated in the inner Solar System, in this perspective the Sun can be seen in the background. (Credit: MPS / Mark A. Garlick) In A Nutshell * Inner Solar System origins: By measuring iron isotopes in Moon rocks and meteorites, researchers determined Theia probably formed closer to the Sun than Earth did, not in the distant outer Solar System. * Identical twins: Earth and the Moon have virtually identical chemical signatures, but both fall outside the range of any meteorites we’ve found—suggesting they incorporated exotic material from...

Explanation: What did Comet Lemmon look like when it was at its best? One example is pictured here, featuring three celestial spectacles all at different distances. The closest spectacle is the snowcapped Meili Mountains, part of the Himalayas in China. The middle marvel is Comet Lemmon near its picturesque best early this month, showing not only a white dust tail trailing off to the right but its blue solar wind-distorted ion tail trailing off to the left. Far in the distance on the left is the magnificent central plane of our Milky Way Galaxy, featuring dark dust, red nebula, and...

Explanation: It's only 50 light-years to 51 Pegasi. That star's position is indicated in this snapshot from August 2025, taken on a night with mostly brighter stars visible above the dome at Observatoire de Haute-Provence in France. Thirty years ago, in October of 1995, astronomers Michel Mayor and Didier Queloz announced a profound discovery made at the observatory. Using a precise spectrograph, they had detected a planet orbiting 51 Peg, the first known exoplanet orbiting a sun-like star. Mayor and Queloz had used the spectrograph to measure changes in the star's radial velocity, a regular wobble caused by the gravitational...

Explanation: What created this unusual space sculpture? Stars. This unusual system of swirls and shells, known as Apep, was observed in unprecedented detail by NASA’s James Webb Space Telescope in infrared light in 2024. Observations indicate that the unusual shape originates from two massive Wolf-Rayet stars orbiting each other every 190 years with each close passes causing a new shell of dust and gas to be expelled. Holes in these shells are thought to be caused by a third orbiting star. This stellar dust dance will likely continue for hundreds of thousands of years, possibly ending only when one of...

Explanation: That big, bright, beautiful Full Moon you watched rise on the night of October 6 was the Harvest Moon. Famed in festival, story, and song, Harvest Moon is just the traditional name of the full moon nearest the time of the northern hemisphere's autumnal equinox. According to lore the name is a fitting one. Despite the diminishing daylight hours, as the growing season drew to a close in the north, farmers could harvest crops by the light of a full moon shining on from dusk to dawn. Later this year than usual, in 2025 October's Harvest Moon was also...

Explanation: How far can you see? Everything you can see, and everything you could possibly see, right now, assuming your eyes could detect all types of radiations around you -- is the observable universe. In light, the farthest we can see comes from the cosmic microwave background, a time 13.8 billion years ago when the universe was opaque like thick fog. Some neutrinos and gravitational waves that surround us come from even farther out, but humanity does not yet have the technology to detect them. The featured image illustrates the observable universe on an increasingly compact scale, with the Earth...

Explanation: What powers are being wielded in the Wizard Nebula? Gravitation strong enough to form stars, and stellar winds and radiations powerful enough to create and dissolve towers of gas. Located only 8,000 light years away, the Wizard nebula, featured here, surrounds a developing open star cluster NGC 7380. Visually, the interplay of stars, gas, and dust has created a shape that appears to some like a fictional medieval sorcerer. The active star forming region spans about 100 light years, making it appear larger than the angular extent of the Moon. The Wizard Nebula can be located with a small...

Explanation: Seen to the left of Saturn's banded planetary disk, small icy moons Dione and Rhea are caught passing in front of the gas giant's extensive ring system in this sharp telescopic snapshot. The remarkable image was recorded on November 20, when Saturn's rings were nearly edge-on when viewed from planet Earth. In fact, every 13 to 16 years the view from planet Earth aligns with Saturn's ring plane to produce a series of ring plane crossings. During a ring plane crossing, the interplanetary edge-on perspective makes the thin but otherwise bright rings seem to disappear. By November 23rd Saturn's...

Explanation: Now a second supernova in this same galaxy is repeating. The cause is the gravitational lens effect of a massive foreground cluster of galaxies (MACS J0138) -- it creates multiple images of a perfectly aligned background galaxy (MRG-M0138). What's particularly interesting is that this background galaxy has young stars that keep blowing up. And images of each supernova explosion keep coming to us multiple times through different paths through the cluster. The original lensed supernova set, shown in the rollover, is called Requiem and was first seen by the Hubble Space Telescope in 2016. This second lensed supernova set...

The incredible Apep system as seen in infrared by JWST. Image Credit: NASA, ESA, CSA, STScI; Science: Yinuo Han (Caltech), Ryan White (Macquarie University); Image Processing: Alyssa Pagan (STScI) DOWNLOAD PDF SHARE facebook-icon twitter-icon reddit-icon flipboard-icon bluesky-icon Google prefered source badge From the very first images, JWST showed that it was going to be a revolutionary instrument, and yet it continues to surprise us. New observations from the infrared space telescope have upended previous observations of a relatively close star system. It has revealed a complexity that had not been seen before in spectacularly crisp new images. The aging star...

Explanation: Now outbound after its perihelion or closest approach to the Sun on October 29, Comet 3I/ATLAS is only the third known interstellar object to pass through our fair Solar System. Its greenish coma and faint tails are seen against a background of stars in the constellation Virgo in this view from planet Earth, recorded with a small telescope on November 14. But this interstellar interloper is the subject of an on-going, unprecedented Solar System-wide observing campaign involving spacecraft and space telescopes from Earth orbit to the surface of Mars and beyond. And while the comet from another star-system has...

Explanation: How does a comet tail change? It depends on the comet. The ion tail of Comet C/2025 A6 (Lemmon) has been changing markedly, as detailed in the featured image sequenced over six days between September 25 and October 4 (left to right) from Texas, USA. On some days, the comet's ion tail was relatively more complex than other days. Reasons for tail changes include the rate of ejection of material from the comet's nucleus, the strength and complexity of the passing solar wind, and the rotation rate of the comet. Sometimes, over the course of a week, apparent differences...

Explanation: Alnitak, Alnilam, and Mintaka are the bright bluish stars from east to west (upper right to lower left) along the diagonal in this cosmic vista. Otherwise known as the Belt of Orion, these three blue supergiant stars are hotter and much more massive than the Sun. They lie from 700 to 2,000 light-years away, born of Orion's well-studied interstellar clouds. In fact, clouds of gas and dust adrift in this region have some surprisingly familiar shapes, including the dark Horsehead Nebula and Flame Nebula near Alnitak at the upper right. The famous Orion Nebula itself is off the right...

The ice giant Uranus is pictured shining against the blackness of space. Its blue surface is marked by lighter clouds and an equatorial band, while a large pale cloud hovers over its polar region. A Hubble Space Telescope view of Uranus captured in February 2019 (Image credit: NASA, ESA, and A. Simon (NASA Goddard Space Flight Center), and M. Wong and A. Hsu (University of California, Berkeley)) ============================================================= November is the best month of 2025 to catch a glimpse of the distant ice giant Uranus as it shines at opposition, though you'll still need a telescope if you hope to...

Explanation: It was one of the largest and longest lived storms ever recorded in our Solar System. First seen in late 2010, the featured cloud formation in the northern hemisphere of Saturn started larger than the Earth and soon spread completely around the planet. The storm was tracked not only from Earth but from up close by the robotic Cassini spacecraft then orbiting Saturn. Pictured here in false colored infrared in February, orange colors indicate clouds deep in the atmosphere, while light colors highlight clouds higher up. The rings of Saturn are seen nearly edge-on as the thin blue horizontal...

NASA's big reveal of the mysterious interstellar object has been slammed as a joke, with many claiming the space agency is covering up what they really know.The newest images of the visitor, known as 3I/ATLAS, were released by the space agency on Wednesday.However, the pictures, taken on a rather sophisticated camera on Mars, were largely blurry and showed only a distant dot.Moreover, NASA refuted any claims that the object, which had made unexpected maneuvers that dumbfounded experts, is anything other than a large space rock.>>>'What a waste of time! NASA is lying so bad. They are all so scripted. The...

Explanation: Sometimes the dark dust of interstellar space has an angular elegance. Such is the case toward the far-south constellation of Chamaeleon. Normally too faint to see, dark dust is best known for blocking visible light from stars and galaxies behind it. In this 11.4-hour exposure, however, the dust is seen mostly in light of its own, with its strong red and near-infrared colors creating a brown hue. Contrastingly blue, a bright star Beta Chamaeleontis is visible on the upper right of the V, with the dust that surrounds it preferentially reflecting blue light from its primarily blue-white color. All...

Explanation: No one on Earth sees the Moon rotate like this. That's because the Moon is tidally locked in synchronous rotation, showing only one side to denizens of our fair planet. Still, given modern digital technology, combined with many detailed images returned by the Lunar Reconnaissance Orbiter (LRO), a high resolution virtual Moon rotation movie can be composed. In fact, the featured time-lapse video starts with a view of the familiar lunar nearside and quickly finds the Mare Orientale, a large crater with a dark center that is difficult to see from the Earth, rotating into view just below the...

Explanation: What does the Milky Way look like in radio waves? To better find out, GLEAM surveyed the central band of our galaxy in high resolution radio light as imaged by the Murchison Widefield Array in Australia. As the featured video slowly scrolls, radio light (71 - 231 MHz) is seen on the left and visible light -- from the same field -- on the right. Differences are so great because most objects glow differently in radio and visible light, and because visible light is stopped by nearby interstellar dust. These differences are particularly apparent in the direction toward the...

Explanation: This deep field mosaicked image presents a stunning view of galaxy cluster Abell 2744 recorded by the James Webb Space Telescope's NIRCam. Also dubbed Pandora's Cluster, Abell 2744 itself appears to be a ponderous merger of three different massive galaxy clusters. It lies some 3.5 billion light-years away, toward the constellation Sculptor. Dominated by dark matter, the mega-cluster warps and distorts the fabric of spacetime, gravitationally lensing even more distant objects. Redder than the Pandora cluster galaxies, many of the lensed sources are very distant galaxies in the early Universe, their lensed images stretched and distorted into arcs. Of...