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Comet Lemmon is brightening and moving into morning northern skies. Besides Comet SWAN25B and Comet ATLAS , Comet C/2025 A6 (Lemmon) is now the third comet currently visible with binoculars and on long camera exposures. Comet Lemmon was discovered early this year and is still headed into the inner Solar System . The comet will round the Sun on November 8, but first it will pass its nearest to the Earth -- at about half the Earth-Sun distance -- on October 21. Although the brightnesses of comets are notoriously hard to predict , optimistic estimates have Comet Lemmon then becoming visible to the unaided eye. The comet should be best seen in predawn skies until mid-October, when it also becomes visible in evening skies. The featured image showing the comet's split and rapidly changing ion tail was taken in Texas , USA late last week. from NASA https://ift.tt/MPm1p3s

It may look like these comets are racing, but they are not. Comets C/2025 K1 ATLAS (left) and C/2025 R2 SWAN (right) appeared near each other by chance last week in the featured image taken from France's Reunion Island in the southern Indian Ocean . Fainter Comet ATLAS is approaching our Sun and will reach its closest approach in early October when it is also expected to be its brightest -- although still only likely visible with long exposures on a camera. The brighter comet, nicknamed SWAN25B , is now headed away from our Sun , although its closest approach to Earth is expected in mid-October, when optimistic estimates have it becoming bright enough to see with the unaided eye. Each comet has a greenish coma of expelled gas and an ion tail pointing away from the Sun. from NASA https://ift.tt/bvJaqmN

What is creating these unusual spots? Light-colored spots on Martian rocks , each surrounded by a dark border, were discovered last year by NASA 's Perseverance Rover currently exploring Mars . Dubbed leopard spots because of their seemingly similarity to markings on famous Earth-bound predators , these curious patterns are being studied with the possibility they were created by ancient Martian life . The pictured spots measure only millimeter s across and were discovered on a larger rock named Cheyava Falls . The exciting but unproven speculation is that long ago, microbe s generated energy with chemical reactions that turned rock from red to white while leaving a dark biosignature ring, like some similarly appearing spots on Earth rocks . Although other non-biological explanations have not been ruled out, speculation focusing on this potential biological origin is causing much intrigue . from NASA https://ift.tt/yYoldgq

On the morning of September 24 a rocket crosses the bright solar disk in this long range telescopic snapshot captured from Orlando, Florida. That's about 50 miles north of its Kennedy Space Center launch site. This rocket carried three new space weather missions to space. Signals have now been successfully acquired from all three - NASA's Interstellar Mapping and Acceleration Probe, NASA’s Carruthers Geocorona Observatory, and the National Oceanic and Atmospheric Administration (NOAA) Space Weather Follow-On Lagrange 1 (SWFO-L1) - as they begin their journey to L1, an Earth-Sun lagrange point. L1 is about 1.5 million kilometers in the sunward direction from planet Earth. Appropriately, major space weather influencers, aka dark sunspots in active regions across the Sun, are posing with the transiting rocket. In fact, large active region AR4225 is just right of the rocket's nose. from NASA https://ift.tt/neWrOZF

A new visitor to the inner Solar System, comet C/2025 R2 (SWAN) sports a long ion tail extending diagonally across this almost 7 degree wide telescopic field of view recorded on September 21 . A fainter fellow comet also making its inner Solar System debut, C/2025 K1 (ATLAS) , can be spotted above and left of SWAN's greenish coma, just visible against the background sea of stars in the constellation Virgo. Both new comets were only discovered in 2025 and are joined in this celestial frame by ruddy planet Mars (bottom), a more familiar wanderer in planet Earth's night skies. The comets may appear to be in a race, nearly neck and neck in their voyage through the inner Solar System and around the Sun. But this comet SWAN has already reached its perihelion or closest approach to the Sun on September 12 and is now outbound along its orbit. This comet ATLAS is still inbound though, and will make its perihelion passage on October 8. from NASA https://ift.tt/v4nYWom

This year Saturn was at opposition on September 21, opposite the Sun in planet Earth's sky. At its closest to Earth, Saturn was also at its brightest of the year, rising as the Sun set and shining above the horizon all night long among the fainter stars of the constellation Pisces. In this snapshot from the Qinghai Lenghu Observatory , Tibetan Plateau, southwestern China, the outer planet is immersed in a faint, diffuse oval of light known as the gegenschein or counter glow. The diffuse gegenschein is produced by sunlight backscattered by interplanetary dust along the Solar System's ecliptic plane , opposite the Sun in planet Earth's sky. Like a giant eye, on this dark night Saturn and gegenschein seem to stare down on the observatory's telescope domes seen against a colorful background of airglow along the horizon. from NASA https://ift.tt/BE3QUXL

It was the strongest gravitational wave signal yet measured -- what did it show? GW250114 was detected by both arms of the Laser Interferometer Gravitational-wave Observatory (LIGO) in Washington and Louisiana USA earlier this year. Analysis showed that the event was created when two black holes , each of mass around 33 times the mass of the Sun , coalesced into one larger black hole with a mass of around 63 solar masses. Even though the event happened about a billion light years away, the signal was so strong that the spin of all black holes , as well as initial ringing of the final black hole, was deduced with exceptional accuracy . Furthermore, it was confirmed better than before, as previously predicted , that the total event horizon area of the combined black hole was greater than those of the merging black holes . Featured, an artist's illustration depicts an imaginative and conceptual view from near one of the black holes before collision. from NASA https://ift.t...

How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun , making it one of the most massive stars known. This star is the brightest object located in the central cavity near the bottom center of the featured image taken with the Webb Space Telescope in infrared light. For comparison, a rollover image from the Hubble Space Telescope is also featured in visible light. Close inspection of the images , however, has shown that Pismis 24-1 derives its brilliant luminosity not from a single star but from three at least. Component stars would still remain near 100 solar masses, making them among the more massive stars currently on record. Toward the bottom of the image, stars are still forming in the associated emission nebula NGC 6357 . Appearing perhaps like a Gothic cathedral , energetic stars near the center appear to be breaking out and illu...

On Saturn, the rings tell you the season. On Earth , today marks an equinox, the time when the Earth's equator tilts directly toward the Sun. Since Saturn's grand rings orbit along the planet's equator, these rings appear most prominent -- from the direction of the Sun -- when the spin axis of Saturn points toward the Sun . Conversely, when Saturn 's spin axis points to the side, an equinox occurs, and the edge-on rings are hard to see from not only the Sun -- but Earth . In the featured montage , images of Saturn between the years of 2020 and 2025 have been superposed to show the giant planet passing, with this year's equinox, from summer in the north to summer in the south. Yesterday , Saturn was coincidently about as close as it gets to planet Earth, and so this month the ringed giant's orb is relatively bright and visible throughout the night. from NASA https://ift.tt/Qn7sJde

Does the Sun set in the same direction every day? No, the direction of sunset depends on the time of the year. Although the Sun always sets approximately toward the west, on an equinox like today the Sun sets directly toward the west . After tomorrow's September equinox, the Sun will set increasingly toward the southwest, reaching its maximum displacement at the December solstice . Before today's September equinox, the Sun had set toward the northwest, reaching its maximum displacement at the June solstice . The featured time-lapse image shows seven bands of the Sun setting one day each month from 2019 December through 2020 June. These image sequences were taken from Alberta , Canada -- well north of the Earth's equator -- and feature the city of Edmonton in the foreground. The middle band shows the Sun setting during the last equinox -- in March. From this location , the Sun will set along this same equinox band again tomorrow. from NASA https://ift.tt/PCFUaoJ

Early risers around planet Earth have enjoyed a shining crescent Moon near brilliant Venus, close to the eastern horizon in recent morning twilight skies. And yesterday, on September 19, skygazers watching from some locations in Earth's northern hemisphere were also able to witness Venus, in the inner planet's waxing gibbous phase , pass behind the Moon's waning crescent . In fact, this telescopic snapshot was taken moments before that occultation of gibbous Venus by the crescent Moon began. The close-up view of the beautiful celestial alignment records Venus approaching part of the Moon's sunlit edge in clear daytime skies from the Swiss Alps. Tomorrow , the Sun will pass behind a New Moon. But to witness that partial solar eclipse on September 21, skygazers will need to watch from locations in planet Earth's southern hemisphere. from NASA https://ift.tt/WRSHCLl

How does your favorite planet spin? Does it spin rapidly around a nearly vertical axis, or horizontally, or backwards? The featured video animates NASA images of all eight planets in our Solar System to show them spinning side-by-side for an easy comparison. In the time-lapse video , a day on Earth -- one Earth rotation -- takes just a few seconds. Jupiter rotates the fastest, while Venus spins not only the slowest (can you see it?), but backwards. The inner rocky planets across the top underwent dramatic spin-altering collisions during the early days of the Solar System. Why planets spin and tilt as they do remains a topic of research with much insight gained from modern computer modeling and the recent discovery and analysis of hundreds of exoplanets : planets orbiting other stars . from NASA https://ift.tt/FGL4JM7

The steerable 60 foot diameter dish antenna of the One-Mile Telescope at Mullard Radio Astronomy Observatory , Cambridge, UK, is pointing skyward in this evocative night-skyscape. To capture the dramatic scene, consecutive 30 second exposures were recorded over a period of 90 minutes. Combined, the exposures reveal a background of gracefully arcing star trails that reflect planet Earth's daily rotation on its axis . The North Celestial Pole , the extension of Earth's axis of rotation into space, points near Polaris, the North Star . That's the bright star that creates the short trail near the center of the concentric arcs . But the historic One-Mile Telescope array also relied on planet Earth's rotation to operate. Exploring the universe at radio wavelengths , it was the first radio telescope to use Earth-rotation aperture synthesis. That technique uses the rotation of the Earth to change the relative orientation of the telescope array and celestial radio sources to...

September's total lunar eclipse is tracked across night skies from both the northern and southern hemispheres of planet Earth in these two dramatic timelapse series. In the northern hemisphere sequence (top panel) the Moon’s trail arcs from the upper left to the lower right. It passes below bright planet Saturn, seen under mostly clear skies from the international campus of Zhejiang University in China at about 30 degrees north latitude. In contrast, the southern hemisphere view from Lake Griffin, Canberra, Australia at 35 degrees south latitude, records the Moon’s trail from the upper right to the lower left. Multiple lightning flashes from thunderstorms near the horizon appear reflected in the lake. Both sequences were photographed with 16mm wide-angle lenses and both cover the entire eclipse , with the darkened red Moon totally immersed in Earth's umbral shadow near center. But the different orientations of the Moon’s path across the sky reveal the perspective shifts ca...

The dark, inner shadow of planet Earth is called the umbra . Shaped like a cone extending into space, it has a circular cross section most easily seen during a lunar eclipse . And on the night of September 7/8 the Full Moon passed near the center of Earth's umbral cone, entertaining eclipse watchers around much of our fair planet, including parts of Antarctica, Australia, Asia, Europe, and Africa. Recorded from Zhangjiakou City, China, this timelapse composite image uses successive pictures from the total lunar eclipse , progressing left to right, to reveal the curved cross-section of the umbral shadow sliding across the Moon. Sunlight scattered by the atmosphere into Earth's umbra causes the lunar surface to appear reddened during totality. But close to the umbra's edge, the limb of the eclipsed Moon shows a distinct blue hue. The blue eclipsed moonlight originates as rays of sunlight pass through layers high in the upper stratosphere, colored by ozone that scatters r...

It is one of the largest nebulas on the sky -- why isn't it better known? Roughly the same angular size as the Andromeda Galaxy , the Great Lacerta Nebula can be found toward the constellation of the Lizard (Lacerta) . The emission nebula is difficult to see with wide-field binoculars because it is so faint , but also usually difficult to see with a large telescope because it is so great in angle -- spanning about three degrees . The depth, breadth, waves , and beauty of the nebula -- cataloged as Sharpless 126 (Sh2-126) -- can best be seen and appreciated with a long duration camera exposure . The featured image is one such combined exposure -- in this case taken over three nights in August through dark skies in Moses Lake , Washington , USA . The hydrogen gas in the Great Lacerta Nebula glows red because it is excited by light from the bright star 10 Lacertae , one of the bright blue stars just to the left of the red-glowing nebula's center. Most of the stars and nebula...

What's that rising up from the Earth? When circling the Earth on the International Space Station early in July , astronaut Nicole Ayers saw an unusual type of lightning rising up from the Earth: a gigantic jet . The powerful jet appears near the center of the featured image in red, white, and blue. Giant jet lightning has only been known about for the past 25 years. The atmospheric jets are associated with thunderstorms and extend upwards towards Earth's ionosphere . The lower part of the frame shows the Earth at night , with Earth's thin atmosphere tinted green from airglow. City lights are visible, sometimes resolved, but usually creating diffuse white glows in intervening clouds. The top of the frame reveals distant stars in the dark night sky. The nature of gigantic jets and their possible association with other types of Transient Luminous Events (TLEs) such as blue jets and red sprites remain active topics of research . from NASA https://ift.tt/uKfw4s9

This butterfly can hatch planets. The nebula fanning out from the star IRAS 04302+2247 may look like the wings of a butterfly , while the vertical brown stripe down the center may look like the butterfly's body -- but together they indicate an active planet-forming system . The featured picture was captured recently in infrared light by the Webb Space Telescope . Pictured, the vertical disk is thick with the gas and dust from which planets form. The disk shades visible and (most) infrared light from the central star, allowing a good view of the surrounding dust that reflects out light. In the next few million years, the dust disk will likely fragment into rings through the gravity of newly hatched planets. And a billion years from now , the remaining gas and dust will likely dissipate, leaving mainly the planets -- like in our Solar System . from NASA https://ift.tt/gCaPQs3

How much of planet Earth is made of water? Very little, actually. Although oceans of water cover about 70 percent of Earth's surface, these oceans are shallow compared to the Earth's radius. The featured illustration shows what would happen if all of the water on or near the surface of the Earth were bunched up into a ball . The radius of this ball would be only about 700 kilometers, less than half the radius of the Earth's Moon , but slightly larger than Saturn's moon Rhea which, like many moons in our outer Solar System , is mostly water ice. The next smallest ball depicts all of Earth 's liquid fresh water, while the tiniest ball shows the volume of all of Earth's fresh-water lake s and river s. How any of this water came to be on the Earth and whether any significant amount is trapped far beneath Earth 's surface remain topic s of research. from NASA https://ift.tt/x4o6cXC

When the sun sets on September 7 , the Full Moon will rise. And on that date denizens around much of our fair planet, including parts of Antarctica, Australia, Asia, Europe, and Africa can witness a total lunar eclipse, with the Moon completely immersed in Earth's shadow. As the bright Full Moon first enters Earth's shadow it will darken, finally taking on a reddish hue during the total eclipse phase. In fact, the color of the Moon during a total lunar eclipse is due to reddened light from sunrises and sunsets around planet Earth . The reddened sunlight is scattered by a dense atmosphere into the planet's otherwise dark central shadow. When the sun set on August 22, this telephoto snapshot of red skies, blue sea, and the Mangiabarche Lighthouse was captured from Sant'Antioco, Sardinia, Italy. from NASA https://ift.tt/G8FEJCR

Also known as NGC 104 , 47 Tucanae is a jewel of the southern sky. Not a star but a dense cluster of stars, it roams the halo of our Milky Way Galaxy along with some 200 other globular star clusters . The second brightest globular cluster (after Omega Centauri ) as seen from planet Earth, 47 Tuc lies about 13,000 light-years away. It can be spotted with the naked eye close on the sky to the Small Magellanic Cloud in the constellation of the Toucan . The dense cluster is made up of hundreds of thousands of stars in a volume only about 120 light-years across. Red giant stars on the outskirts of the cluster are easy to pick out as yellowish stars in this sharp telescopic portrait . Tightly packed globular star cluster 47 Tuc is also home to a star with the closest known orbit around a black hole . from NASA https://ift.tt/lJYAkie

Magnificent spiral galaxy NGC 4565 is viewed edge-on from planet Earth. Also known as the Needle Galaxy for its narrow profile, bright NGC 4565 is a stop on many telescopic tours of the northern sky, in the faint but well-groomed constellation Coma Berenices . This sharp, colorful image reveals the galaxy's boxy, bulging central core cut by obscuring dust lanes that lace NGC 4565's thin galactic plane. NGC 4565 lies around 40 million light-years distant while the spiral galaxy itself spans some 100,000 light-years. That's about the size of our own Milky Way. Easily spotted with small telescopes, deep sky enthusiasts consider NGC 4565 to be a prominent celestial masterpiece Messier missed . from NASA https://ift.tt/1MuzaRQ

How soon do jets form when a supernova gives birth to a neutron star? The Africa Nebula provides clues. This supernova remnant surrounds Circinus X-1 , an X-ray emitting neutron star and the companion star it orbits. The image, from the ThunderKAT collaboration on the MeerKAT radio telescope situated in South Africa , shows the bright core-and-lobe structure of Cir X-1 ’s currently active jets inside the nebula. A mere 4600 years old, Cir X-1 could be the "Little Sister" of microquasar SS 433 *. However, the newly discovered bubble exiting from a ring-like hole in the upper right of the nebula, along with a ring to the bottom left, demonstrate that other jets previously existed. Computer simulations indicate those jets formed within 100 years of the explosion and lasted up to 1000 years. Surprisingly , to create the observed bubble, the jets need to be more powerful than young neutron star s were previously thought to produce. from NASA https://ift.tt/PFpUwfY

The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the orange emission nebula at the far right of the featured picture . The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright emission nebula . Like clouds in Earth's atmosphere , this cosmic cloud has assumed a recognizable shape by chance. After many thousands of years , the internal motions of the cloud will surely alter its appearance. The emission nebula 's orange color is caused by electrons recombining with protons to form hydrogen atoms. Toward the lower left of the image is the Flame Nebula , an orange-tinged nebula that also contains intricate filaments of dark dust. from NASA https://ift.tt/qIubBec

Its surface is the most densely cratered in the Solar System -- but what's inside? Jupiter 's moon Callisto is a battered ball of dirty ice that is larger than the planet Mercury . It was visited by NASA's Galileo spacecraft in the 1990s and 2000s, but the recently reprocessed featured image is from a flyby of NASA's Voyager 2 in 1979. The moon would appear darker if it weren't for the tapestry of light-colored fractured surface ice created by eons of impacts. The interior of Callisto is potentially even more interesting because therein might lie an internal layer of liquid water. This potential underground sea is a candidate to harbor life -- similar with sister moons Europa and Ganymede . Callisto is slightly larger than Luna , Earth's Moon , but because of its high ice content is slightly less massive. ESA's JUICE and NASA's Europa Clipper missions are now headed out to Jupiter to better investigate its largest moons . from NASA https:/...

What created this unusual planetary nebula? Dubbed the Pillow Nebula and the Flying Carpet Nebula, NGC 7027 is one of the smallest, brightest, and most unusually shaped planetary nebula s known. Given its expansion rate, NGC 7027 first started expanding, as visible from Earth, about 600 years ago. For much of its history, the planetary nebula has been expelling shells, as seen in blue in the featured image by the Hubble Space Telescope . In modern times, though, for reasons unknown , it began ejecting gas and dust (seen in brown) in specific directions that created a new pattern that seems to have four corners . What lies at the nebula's center is unknown, with one hypothesis holding it to be a close binary star system where one star sheds gas onto an erratic disk orbiting the other star. NGC 7027, about 3,000 light years away, was first discovered in 1878 and can be seen with a standard backyard telescope toward the constellation of the Swan ( Cygnus ). from NASA https:...

A young crescent moon can be hard to see . That's because when the Moon shows it's crescent phase (young or old) it can never be far from the Sun in planet Earth's sky . And even though the sky is still bright, a slender sunlit lunar crescent is cleary visible in this early evening skyscape . The telephoto snapshot was captured on August 24, with the Moon very near the western horizon at sunset. Seen in a narrow crescent phase about 1.5 days old, the visible sunlit portion is a mere two percent of the surface of the Moon's familiar nearside. At the Canary Islands Space Centre , a steerable radio dish for communication with spacecraft is titled in the direction of the two percent Moon. The sunset sky's pastel pinkish coloring is partly due to fine sand and dust from the Sahara Desert blown by the prevailing winds. from NASA https://ift.tt/A25tY0T

The diffuse hydrogen-alpha glow of emission region Sh2-27 fills this cosmic scene. The field of view spans nearly 3 degrees across the nebula-rich constellation Ophiuchus toward the central Milky Way . A Dark Veil of wispy interstellar dust clouds draped across the foreground is chiefly identified as LDN 234 and LDN 204 from the 1962 Catalog of Dark Nebulae by American astronomer Beverly Lynds . Sh2-27 itself is the large but faint HII region surrounding runaway O-type star Zeta Ophiuchi. Along with the Zeta Oph HII region, LDN 234 and LDN 204 are likely 500 or so light-years away. At that distance, this telescopic frame would be about 25 light-years wide. from NASA https://ift.tt/J4DPElp

This well-composed telescopic field of view covers over a Full Moon on the sky toward the high-flying constellation Pegasus. Of course the brighter stars show diffraction spikes , the commonly seen effect of internal supports in reflecting telescopes , and lie well within our own Milky Way galaxy . The faint but pervasive clouds of interstellar dust ride above the galactic plane and dimly reflect the Milky Way's starlight. Known as galactic cirrus or integrated flux nebulae they are associated with the Milky Way's molecular clouds. In fact, the diffuse cloud cataloged as MBM 54 , less than a thousand light-years distant, fills the scene. The galaxy seemingly tangled in the dusty cloud is the striking spiral galaxy NGC 7497. It's some 60 million light-years away, though. Seen almost edge-on near the center of the field, NGC 7497's own spiral arms and dust lanes echo the colors of stars and dust in our own Milky Way . from NASA https://ift.tt/0OImxqo

That yellow spot -- what is it? It's a young planet outside our Solar System. The featured image from the Very Large Telescope in Chile surprisingly captures a distant scene much like our own Solar System's birth, some 4.5 billion years ago. Although we can't look into the past and see Earth's formation directly, telescopes let us watch similar processes unfolding around distant stars. At the center of this frame lies a young Sun-like star, hidden behind a coronagraph that blocks its bright glare. Surrounding the star is a bright, dusty protoplanetary disk -- the raw material of planets. Gaps and concentric rings mark where a newborn world is gathering gas and dust under its gravity, clearing the way as it orbits the star. Although astronomers have imaged disk-embedded planets before, this is the first-ever observation of an exoplanet actively carving a gap within a disk -- the earliest direct glimpse of planetary sculpting in action. from NASA https://if...

Sometimes even the sky surprises you. To see more stars and faint nebulosity in the Pleiades star cluster ( M45 ), long exposures are made. Many times, less interesting items appear on the exposures that were not intended -- but later edited out. These include stuck pixel s, cosmic ray hits, frames with bright clouds or Earth's Moon , airplane trails , lens flares , faint satellite trails , and even insect trail s. Sometimes, though, something really interesting is caught by chance. That was just the case a few weeks ago in al-Ula , Saudi Arabia when a bright meteor streaked across during an hour-long exposure of the Pleiades . Along with the famous bright blue stars , less famous and less bright blue stars, and blue-reflecting dust surrounding the star cluster, the fast rock fragment created a distinctive green glow, likely due to vaporized metals. from NASA https://ift.tt/Ny7GWVb

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 the emission from the nebula, driving a shock wave through surrounding material and accelerating the spiraling electrons. With more mass than the Sun and the density of an atomic nucleus ,the spinning pulsar is the collapsed core of a massive star that exploded . The outer parts of the Crab Nebula are the expanding remnants of the star's component gases. The supernova ...

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 sea and skyscape, August's rising Full Moon still appears small enough to be caught in the nets of an ancient fishing rig. The telephoto snapshot was taken along the Italian Costa dei Trabocchi , on the Adriatic Sea. from NASA https://ift.tt/unmCzs8

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 as a spiral nebula . By chance the pair are in the same field of view, and while they appear to have similar sizes they are actually very far apart. At a distance of a mere 2,000 light-years M57 is well within our own Milky Way galaxy. Extragalactic IC 1296 (aka PGC62532) is more like 200,000,000 light-years distant. That's about 100,000 times farther away than M57 but since they appear rou...

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 base frame exposure. But all exposures were taken during a period of around 2.5 hours from a wind farm near Mönchhof, Burgenland, Austria. Red lights on the individual wind turbine towers dot the foreground. In their spectacular close conjunction , bright planets Jupiter and Venus are poised above the eastern horizon . from NASA https://ift.tt/jX5aBr0

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 a deep image of the background sky that brought up the central band of our Milky Way galaxy running nearly vertically through the featured image 's center. The limestone arch in the foreground in Dorset , England is known as Durdle Door , a name thought to survive from a thousand years ago. from NASA https://ift.tt/5D172fX

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 nearby smaller galaxy IC 4970 , visible here below the giant spiral galaxy's core. Other members of the southern Pavo galaxy group are scattered through this magnificent galaxy group portrait , with the dominant giant elliptical galaxy, NGC 6876, above and right of the soaring Condor galaxy. from NASA https://ift.tt/nuqm1iT

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-year s, 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 the calibration of the expansion of the Universe. Still, after you get over this beautiful galaxy's grand design, check out the array of more distant background galaxies also recorded in this sharp image from the Hubble Space Telescope . from NASA https://ift.tt/v6CYgxD

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 -- a type of dry downward wind that flows off mountains. Clouds from such a wind called the Canterbury arch stream toward the east coast of New Zealand's South Island . The featured image , taken above Hanmer Springs in Canterbury , New Zealand in 2005, shows great detail partly because sunlight illuminates the un...

The camera battery died about 2am local time on August 12, while shooting in the bright moonlit skies from a garden in Chastre, Brabant Wallon, Belgium, planet Earth. But not before it captured the frames used to compose this cool animated gif of a brilliant Perseid meteor and a lingering visible trail known as a persistent train . The Perseid meteor, a fast moving speck of dust from the tail of large periodic Comet Swift-Tuttle , was heated to incandescence by ram pressure and vaporized as it flashed through the upper atmosphere at 60 kilometers per second . Compared to the brief flash of the meteor, its wraith-like trail really is persistent. A characteristic of bright meteors, a smoke-like persistent train can often be followed for many minutes wafting in the winds at altitudes of 60 to 90 kilometers. from NASA https://ift.tt/qLefHnN

In the predawn sky on August 13, two planets were close. And despite the glare of a waning gibbous Moon, bright Jupiter and even brighter Venus were hard to miss. Their brilliant close conjunction is posing above the eastern horizon in this early morning skyscape. The scene was captured in a single exposure from a site near Gansu, China, with light from both planets reflected in the still waters of a local pond. Also seen against the moonlight were flashes from the annual Perseid Meteor Shower , known for its bright, fast meteors. Near the much anticipated peak of activity, the shower meteors briefly combined with the two planets for a celestial spectacle even in moonlit skies. from NASA https://ift.tt/Kdfw8JV

In 1716 , English astronomer Edmond Halley noted, "This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent." Of course, M13 is now less modestly recognized as the Great Globular Cluster in Hercules, one of the brightest globular star clusters in the northern sky. Sharp telescopic views like this one reveal the spectacular cluster's hundreds of thousands of stars. At a distance of 25,000 light-years, the cluster stars crowd into a region 150 light-years in diameter. Approaching the cluster core, upwards of 100 stars could be contained in a cube just 3 light-years on a side. For comparison with our neighborhood of the Milky Way, the closest star to the Sun is over 4 light-years away. Early telescopic observers of the great globular cluster also noted a curious convergence of three dark lanes with a spacing of about 120 degrees, seen here just below the cluster center. Known as the propeller in M13 , the shape is l...

What lies in the heart of Orion? Trapezium: four bright stars, that can be found near the center of this sharp cosmic portrait . Gathered within a region about 1.5 light-years in radius, these stars dominate the core of the dense Orion Nebula Star Cluster. Ultraviolet ionizing radiation from the Trapezium stars , mostly from the brightest star Theta-1 Orionis C powers the complex star forming region's entire visible glow. About three million years old, the Orion Nebula Cluster was even more compact in its younger years and a dynamical study indicates that runaway stellar collisions at an earlier age may have formed a black hole with more than 100 times the mass of the Sun . The presence of a black hole within the cluster could explain the observed high velocities of the Trapezium stars . The Orion Nebula's distance of some 1,500 light-years make it one of the closest candidate black holes to Earth. from NASA https://ift.tt/XgPaCHs

Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Perseus. That is why the meteor shower that peaks tonight is known as the Perseids -- the meteors all appear to come from a radiant toward Perseus . In terms of parent body, though, the sand-sized debris that makes up the Perseids meteors come from Comet Swift-Tuttle . The comet follows a well-defined orbit around our Sun, and the part of the orbit that approaches Earth is superposed in front of Perseus. Therefore, when Earth crosses this orbit, the radiant point of falling debris appears in Perseus. Featured here , a composite image taken over six nights and containing over 100 meteors from 2024 August Perseids meteor shower shows many bright meteor s that streaked over the Bieszczady Mountains in Poland . This year's Perseids , usually one of the best meteor showers of the year, will compete with a bright moon that will rise , for many locations, s...

What's that strange light down the road? Dust orbiting the Sun. At certain times of the year, a band of sun-reflecting dust from the inner Solar System appears prominently just after sunset -- or just before sunrise -- and is called zodiacal light . Although the origin of this dust is still being researched, a leading hypothesis holds that zodiacal dust originates mostly from faint Jupiter-family comets and slowly spirals into the Sun . Recent analysis of dust emitted by Comet 67P , visited by ESA's robotic Rosetta spacecraft , bolsters this hypothesis. Pictured when climbing a road up to Teide National Park in the Canary Islands of Spain , a bright triangle of zodiacal light appeared in the distance soon after sunset. Captured on June 21, 2019, the scene includes bright Regulus , the alpha star of the constellation Leo, standing above center toward the left. The Beehive Star Cluster (M44) can be spotted below center, closer to the horizon and also immersed in the z...

Discovered on July 1 with the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, 3I/ATLAS is so designated as the third known interstellar object to pass through our Solar System. It follows 1I/ʻOumuamua in 2017 and the comet 2I/Borisov in 2019. Also known as C/2025 N1 , 3I/ATLAS is a comet. A teardrop-shaped cloud of dust, ejected from its icy nucleus warmed by increasing sunlight, is seen in this sharp image from the Hubble Space Telescope captured on July 21. Background stars are streaked in the exposure as Hubble tracked the fastest comet ever recorded on its journey toward the inner solar system. An analysis of the Hubble image indicates the solid nucleus, hidden from direct view, is likely less that 5.6 kilometers in diameter. This comet's interstellar origin is clear from its orbit , determined to be an eccentric, highly hyperbolic orbit that does not loop back around the Sun and will return 3I/ATLAS to interste...

One of the all-time historic skyscapes occured in July 1054, when the Crab Supernova blazed into the dawn sky. Chinese court astrologers first saw the Guest Star on the morning of 4 July 1054 next to the star Tianguan (now cataloged as Zeta Tauri ). The supernova peaked in late July 1054 a bit brighter than Venus, and was visible in the daytime for 23 days. The Guest Star was so bright that every culture around the world inevitably discovered the supernova independently, although only nine reports survive, including those from China, Japan , and Constantinople . This iPhone picture is from Signal Hill near Tucson on the morning of 26 July 2025, faithfully re-creates the year 1054 Dawn of the Crab, showing the sky as seen by Hohokam peoples. The planet Venus, as a stand-in for the supernova , is close to the position of what is now the Crab Nebula supernova remnant. Step outside on a summer dawn with bright Venus, and ask yourself "What would you have thought in ancient ti...

This stunning starfield spans about three full moons (1.5 degrees) across the heroic northern constellation of Perseus . It holds the famous pair of open star clusters , h and Chi Persei. Also cataloged as NGC 869 (right) and NGC 884 , both clusters are about 7,000 light-years away and contain stars much younger and hotter than the Sun. Separated by only a few hundred light-years, the clusters are both 13 million years young based on the ages of their individual stars , evidence that both clusters were likely a product of the same star-forming region. Always a rewarding sight in binoculars or small telescopes, the Double Cluster is even visible to the unaided eye from dark locations . from NASA https://ift.tt/IA49GRJ

What's that green streak in front of the Andromeda galaxy? A meteor. While photographing the Andromeda galaxy in 2016, near the peak of the Perseid Meteor Shower , a small pebble from deep space crossed right in front of our Milky Way Galaxy 's far-distant companion. The small meteor took only a fraction of a second to pass through this 10-degree field. The meteor flared several times while braking violently upon entering Earth's atmosphere . The green color was created, at least in part, by the meteor's gas glowing as it vaporized. Although the exposure was timed to catch a Perseid meteor , the orientation of the imaged streak seems a better match to a meteor from the Southern Delta Aquariids , a meteor shower that peaked a few weeks earlier. Not coincidentally, the Perseid Meteor Shower peaks next week, although this year the meteors will have to outshine a sky brightened by a nearly full moon. from NASA https://ift.tt/0djzbrB