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Why does this large crater on Mercury have two rings and a smooth floor? No one is sure. The unusual feature called Vivaldi Crater spans 215 kilometers and was imaged again in great detail by ESA 's and JAXA 's robotic BepiColombo spacecraft on a flyby earlier this month. A large circular feature on a rocky planet or moon is usually caused by either an impact by a small asteroid or a comet fragment, or a volcanic eruption . In the case of Vivaldi , it is possible that both occurred -- a heavy strike that caused a smooth internal lava flow. Double-ringed craters are rare, and the cause of the inner rings remains a topic of research . The speed-slowing gravity-assist ed flyby of Mercury by BepiColombo was in preparation for the spacecraft entering orbit around the Solar System 's innermost planet in 2026. from NASA https://ift.tt/OIvKgp7

Have you ever seen the Man in the Moon? This common question plays on the ability of humans to see pareidolia -- imagining familiar icons where they don't actually exist. The textured surface of Earth's full Moon is home to numerous identifications of iconic objects, not only in modern western culture but in world folklore throughout history. Examples, typically dependent on the Moon 's perceived orientation, include the Woman in the Moon and the Rabbit in the Moon . One facial outline commonly identified as the Man in the Moon starts by imagining the two dark circular areas -- lunar maria -- here just above the Moon 's center, to be the eyes. Surprisingly, there actually is a man in this Moon image -- a close look will reveal a real person -- with a telescope -- silhouetted against the Moon . This well-planned image was taken in 2016 in Cadalso de los Vidrios in Madrid , Spain . from NASA https://ift.tt/uvytoTa

Only natural colors of the Moon in planet Earth's sky appear in this creative visual presentation. Arranged as pixels in a framed image, the lunar disks were photographed at different times. Their varying hues are ultimately due to reflected sunlight affected by changing atmospheric conditions and the alignment geometry of Moon, Earth, and Sun. Here, the darkest lunar disks are the colors of earthshine . A description of earthshine, in terms of sunlight reflected by Earth's oceans illuminating the Moon's dark surface, was written over 500 years ago by Leonardo da Vinci. But stand farther back from your screen or just shift your gaze to the smaller versions of the image. You might also see one of da Vinci's most famous works of art . from NASA https://ift.tt/NZOBkTI

This snapshot from the International Space Station was taken on August 11 while orbiting about 430 kilometers above the Indian Ocean, Southern Hemisphere, planet Earth . The spectacular view looks south and east, down toward the planet's horizon and through red and green curtains of aurora australis . The auroral glow is caused by emission from excited oxygen atoms in the extremely rarefied upper atmosphere still present at the level of the orbiting outpost. Green emission from atomic oxygen dominates this scene at altitudes of 100 to 250 kilometers, while red emission from atomic oxygen can extend as high as 500 kilometers altitude. Beyond the glow of these southern lights, this view from low Earth orbit reveals the starry sky from a southern hemisphere perspective . Stars in Orion's belt and the Orion Nebula are near the Earth's limb just left of center. Sirius, alpha star of Canis Major and brightest star in planet Earth's night is above center along the right e

This spectacular mosaic of images from the James Webb Space Telescope peers into the heart of young star cluster NGC 1333. A mere 1,000 light-years distant toward the heroic constellation Perseus , the nearby star cluster lies at the edge of the large Perseus molecular cloud. Part of Webb's deep exploration of the region to identify low mass brown dwarf stars and free floating planets, the space telescope's combined field of view spans nearly 2 light-years across the dusty cluster's turbulent stellar nursery. In fact, NGC 1333 is known to harbor stars less than a million years old, though most are hidden from optical telescopes by the pervasive stardust . The chaotic environment may be similar to one in which our own Sun formed over 4.5 billion years ago. from NASA https://ift.tt/6UBlQPo

A natural border between Slovakia and Poland is the Tatra Mountains . A prominent destination for astrophotographers, the Tatras are the highest mountain range in the Carpathians . In the featured image taken in May, one can see the center of our Milky Way galaxy with two of its famous stellar nurseries , the Lagoon and Omega Nebula , just over the top of the Tatras. Stellar nurseries are full of ionized hydrogen , a fundamental component for the formation of Earth-abundant water . As a fundamental ingredient in all known forms of life , water is a crucial element in the Universe . Such water can be seen in the foreground in the form of the Bialka River . from NASA https://ift.tt/vE3RzTc

The dark Horsehead Nebula and the glowing Orion Nebula are contrasting cosmic vistas. Adrift 1,500 light-years away in one of the night sky's most recognizable constellation s, they appear in opposite corners of the above stunning mosaic . The familiar Horsehead nebula appears as a dark cloud, a small silhouette notched against the long glow of hydrogen -- here shown in gold -- at the lower left. Alnitak is the easternmost star in Orion's belt and is seen as the brightest star just below and to the left of the Horsehead . To the left of Alnitak is the Flame Nebula , with clouds of bright emission and dramatic dark dust lanes. The magnificent emission region, the Orion Nebula (aka M42), lies at the upper right. Immediately to its left is a prominent reflection nebula sometimes called the Running Man. Pervasive tendrils of glowing hydrogen gas are easily traced throughout the region. from NASA https://ift.tt/o70Ma8g

If you could fly over Mars, what might you see? The featured image shows exactly this in the form of a Mars Express vista captured over a particularly interesting region on Mars in July. The picture's most famous feature is Olympus Mons , the largest volcano in the Solar System , visible on the upper right. Another large Martian volcano is visible on the right horizon: Pavonis Mons . Several circular impact craters can be seen on the surface of the aptly named red planet . Impressively, this image was timed to capture the dark and doomed Martian moon Phobos , visible just left of center. The surface feature on the lower left, known as Orcus Patera , is unusual for its large size and oblong shape, and mysterious because the processes that created it still remain unknown. ESA 's robotic Mars Express spacecraft was launched in 2003 and, among many notable science discoveries , bolstered evidence that Mars was once home to large bodies of water . from NASA https://ift.

The most distant object easily visible to the unaided eye is M31 , the great Andromeda Galaxy . Even at some two and a half million light-year s distant, this immense spiral galaxy -- spanning over 200,000 light years -- is visible, although as a faint, nebulous cloud in the constellation Andromeda . A bright yellow nucleus, dark winding dust lanes , and expansive spiral arms dotted with blue star cluster s and red nebulae , are recorded in this stunning telescopic image which combines data from orbiting Hubble with ground-based images from Subaru and Mayall . In only about 5 billion years, the Andromeda galaxy may be even easier to see -- as it will likely span the entire night sky -- just before it merges with, or passes right by, our Milky Way Galaxy . from NASA https://ift.tt/mCQJVEc

Mars has two tiny moons, Phobos and Deimos , named for the figures in Greek mythology Fear and Panic. Detailed surface views of smaller moon Deimos are shown in both these panels. The images were taken in 2009 , by the HiRISE camera on board the Mars Reconnaissance Orbiter spacecraft, NASA's long-lived interplanetary internet satellite. The outermost of the two Martian moons, Deimos is one of the smallest known moons in the Solar System, measuring only about 15 kilometers across. Both Martian moons were discovered in 1877 by Asaph Hall , an American astronomer working at the US Naval Observatory in Washington D.C. But their existence was postulated around 1610 by Johannes Kepler , the astronomer who derived the laws of planetary motion. In this case, Kepler's prediction was not based on scientific principles, but his writings and ideas were so influential that the two Martian moons are discussed in works of fiction such as Jonathan Swift 's Gulliver's Travels, writte

Ringed ice giant Neptune lies near the center of this sharp near-infrared image from the James Webb Space Telescope . The dim and distant world is the farthest planet from the Sun , about 30 times farther away than planet Earth. But in the stunning Webb view, the planet's dark and ghostly appearance is due to atmospheric methane that absorbs infrared light. High altitude clouds that reach above most of Neptune's absorbing methane easily stand out in the image though. Coated with frozen nitrogen, Neptune's largest moon Triton is brighter than Neptune in reflected sunlight, seen at the upper left sporting the Webb telescope's characteristic diffraction spikes . Including Triton, seven of Neptune's 14 known moons can be identified in the field of view. Neptune's faint rings are striking in this space-based planetary portrait . Details of the complex ring system are seen here for the first time since Neptune was visited by the Voyager 2 spacecraft in August 1989

About 70,000 light-years across, NGC 247 is a spiral galaxy smaller than our Milky Way. Measured to be only 11 million light-years distant it is nearby though. Tilted nearly edge-on as seen from our perspective , it dominates this telescopic field of view toward the southern constellation Cetus. The pronounced void on one side of the galaxy's disk recalls for some its popular name, the Needle's Eye galaxy. Many background galaxies are visible in this sharp galaxy portrait, including the remarkable string of four galaxies just below and left of NGC 247 known as Burbidge's Chain. Burbidge's Chain galaxies are about 300 million light-years distant. NGC 247 itself is part of the Sculptor Group of galaxies along with shiny spiral NGC 253 . from NASA https://ift.tt/SDgB8pd

Can you see the bat? It haunts this cosmic close-up of the eastern Veil Nebula . The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death explosion of a massive star . While the Veil is roughly circular in shape and covers nearly 3 degrees on the sky toward the constellation of the Swan ( Cygnus ), NGC 6995, known informally as the Bat Nebula, spans only 1/2 degree, about the apparent size of the Moon . That translates to 12 light-years at the Veil's estimated distance, a reassuring 1,400 light-years from planet Earth . In the composite of image data recorded through narrow band filters, emission from hydrogen atoms in the remnant is shown in red with strong emission from oxygen atoms shown in hues of blue. Of course, in the western part of the Veil lies another seasonal apparition: the Witch's Broom Nebula. from NASA https://ift.tt/q6EUrik

Nine days ago, two quite different sky icons were imaged rising together. Specifically, Earth's Moon shared the eastern sky with the sister stars of the Pleiades cluster, as viewed from Alberta , Canada . Astronomical images of the well-known Pleiades often show the star cluster's alluring blue reflection nebula s, but here they are washed-out by the orange moonrise sky. The half-lit Moon, known as a quarter moon , is overexposed, although the outline of the dim lunar night side can be seen by illuminating earthshine , light first reflected from the Earth. The featured image is a composite of eight successive exposures with brightnesses adjusted to match what the human eye would see. The Moon passes nearly -- or directly -- in front of the Pleaides once a month. from NASA https://ift.tt/DTA2lP3

Why is there a triangle hovering over the Sun? Although the shape is unusual, the type of structure is not: it is part of an evolving solar prominence . Looping magnetic fields on the Sun channel the flow of energetic particles, sometimes holding glowing gaseous structures aloft for months. A prominence glows brightly because it contains particularly hot, dense, or opaque solar plasma . The surprising triangular structure occurred last week. Larger than our Earth, the iconic prominence was imaged by several solar photographers and documented by NASA's Solar Dynamic Observatory to form and violently dissipate in about a day. The featured image was captured in a color of red light emitted strongly by hydrogen . Below, solar fibrils carpet the Sun's chromosphere , while the background sky is so faint in comparison that no stars are visible. Our Sun's surface has been quite active this year. from NASA https://ift.tt/yUH3ldh

Why does Saturn appear so big? It doesn't -- what is pictured are foreground clouds on Earth crossing in front of the Moon . The Moon shows a slight crescent phase with most of its surface visible by reflected Earthlight , known as Da Vinci glow . The Sun directly illuminates the brightly lit lunar crescent from the bottom, which means that the Sun must be below the horizon and so the image was taken before sunrise. This double take -inducing picture was captured on 2019 December 24, two days before the Moon slid in front of the Sun to create a solar eclipse . In the foreground, lights from small Guatemala n towns are visible behind the huge volcano Pacaya . from NASA https://ift.tt/9pZ4MgQ

Galaxies of the NGC 7771 Group are featured in this intriguing skyscape . Some 200 million light-years distant toward the constellation Pegasus, NGC 7771 is the large, edge-on spiral near center, about 75,000 light-years across, with two smaller galaxies below it. Large spiral NGC 7769 is seen face-on to the right. Galaxies of the NGC 7771 group are interacting, making repeated close passages that will ultimately result in galaxy-galaxy mergers on a cosmic timescale. The interactions can be traced by distortions in the shape of the galaxies themselves and faint streams of stars created by their mutual gravitational tides. But a clear view of this galaxy group is difficult to come by as the deep image also reveals extensive clouds of foreground dust sweeping across the field of view. The dim, dusty galactic cirrus clouds are known as Integrated Flux Nebulae. The faint IFN reflect starlight from our own Milky Way Galaxy and lie only a few hundred light-years above the galactic plane

The Moon's south pole is toward the top left of this detailed telescopic moonscape . Captured on August 23, it looks across the rugged southern lunar highlands. The view's foreshortened perspective heightens the impression of a dense field of craters and makes the craters themselves appear more oval shaped close to the lunar limb. Prominent near center is 114 kilometer diameter crater Moretus. Moretus is young for a large lunar crater and features terraced inner walls and a 2.1 kilometer high, central peak, similar in appearance to the more northerly young crater Tycho . Mountains visible along the lunar limb at the top can rise about 6 kilometers or so above the surrounding terrain. Close to the lunar south pole, permanently shadowed crater floors with expected reservoirs of water-ice have made the rugged south polar region of the Moon a popular target for exploration . from NASA https://ift.tt/0P5sQ6S

A nearby star factory known as Messier 17 lies some 5,500 light-years away in the nebula-rich constellation Sagittarius . At that distance, this 1.5 degree wide field-of-view would span about 150 light-years. In the sharp color composite image faint details of the region's gas and dust clouds are highlighted with narrowband image data against a backdrop of central Milky Way stars. The stellar winds and energetic radiation from hot, massive stars already formed from M17's stock of cosmic gas and dust have slowly carved away at the remaining interstellar material, producing the nebula's cavernous appearance and the undulating shapes within. A popular stop on telescopic tours of the cosmos, M17 is also known as the Omega or the Swan Nebula. from NASA https://ift.tt/vqL9p18

When can you see a black hole, a tulip, and a swan all at once? At night -- if the timing is right, and if your telescope is pointed in the right direction . The complex and beautiful Tulip Nebula blossoms about 8,000 light-years away toward the constellation of Cygnus the Swan. Ultraviolet radiation from young energetic stars at the edge of the Cygnus OB3 association , including O star HDE 227018, ionizes the atoms and powers the emission from the Tulip Nebula. Stewart Sharpless cataloged this nearly 70 light-years across reddish glowing cloud of interstellar gas and dust in 1959 , as Sh2-101 . Also in the featured field of view is the black hole Cygnus X-1 , which to be a microquasar because it is one of strongest X-ray sources in planet Earth's sky. Blasted by powerful jets from a lurking black hole , its fainter bluish curved shock front is only faintly visible beyond the cosmic Tulip's petals, near the right side of the frame. from NASA https://ift.tt/6WzT2mV

What if Saturn disappeared? Sometimes, it does. It doesn't really go away, though, it just disappears from view when our Moon moves in front . Such a Saturnian eclipse, more formally called an occultation , was visible along a long swath of Earth -- from Peru , across the Atlantic Ocean, to Italy -- only a few days ago. The featured color image is a digital fusion of the clearest images captured during the event and rebalanced for color and relative brightness between the relatively dim Saturn and the comparatively bright Moon. Saturn and the comparative bright Moon . The exposures were all taken from Breda , Catalonia , Spain , just before occultation. Eclipses of Saturn by our Moon will occur each month for the rest of this year. Each time, though, the fleeting event will be visible only to those with clear skies -- and the right location on Earth . from NASA https://ift.tt/04jnMQE

Did you see it? One of the more common questions during a meteor shower occurs because the time it takes for a meteor to flash is similar to the time it takes for a head to turn. Possibly, though, the glory of seeing bright meteors shoot across the sky -- while knowing that they were once small pebbles on another world -- might make it all worthwhile, even if your observing partner(s) can't always share in your experience. The featured video is composed of short clips taken in Inner Mongolia , China during the 2023 Perseid Meteor Shower . Several bright meteors were captured while live-reaction audio was being recorded -- just as the meteors flashed . This year's 2024 Perseids also produced many beautiful meteors . Another good meteor shower to watch for is the Geminids which peak yearly in mid-December, this year with relatively little competing glow from a nearly new Moon. from NASA https://ift.tt/nETdyMX

Do underground oceans vent through canyons on Saturn's moon Enceladus? Long features dubbed tiger stripes are known to be spewing ice from the moon's icy interior into space, creating a cloud of fine ice particles over the moon's South Pole and creating Saturn 's mysterious E-ring . Evidence for this has come from the robot Cassini spacecraft that orbited Saturn from 2004 to 2017. Pictured here , a high resolution image of Enceladus is shown from a close flyby. The unusual surface features dubbed tiger stripes are visible in false-color blue. Why Enceladus is active remains a mystery, as the neighboring moon Mimas , approximately the same size, appears quite dead . An analysis of ejected ice grains has yielded evidence that complex organic molecules exist inside Enceladus. These large carbon-rich molecules bolster -- but do not prove -- that oceans under Enceladus' surface could contain life . from NASA https://ift.tt/rfQcbjy

The full Moon and Earth's shadow set together in this island skyscape. The alluring scene was captured Tuesday morning, August 20, from Fiji, South Pacific Ocean, planet Earth. For early morning risers shadowset in the western sky is a daily apparition . Still, the grey-blue shadow is often overlooked in favor of a brighter eastern horizon. Extending through the dense atmosphere, Earth's setting shadow is bounded above by a pinkish glow or anti-twilight arch . Known as the Belt of Venus, the arch's lovely color is due to backscattering of reddened light from the opposite horizon's rising Sun. Of course, the setting Moon's light is reddened by the long sight-line through the atmosphere. But on that date the full Moon could be called a seasonal Blue Moon, the third full Moon in a season with four full Moons. And even though the full Moon is always impressive near the horizon, August's full Moon is considered by some the first of four consecutive full Supermoon

There is a quiet pulsar at the heart of CTA 1. The supernova remnant was discovered as a source of emission at radio wavelengths by astronomers in 1960 and since identified as the result of the death explosion of a massive star. But no radio pulses were detected from the expected pulsar, the rotating neutron star remnant of the massive star's collapsed core. Seen about 10,000 years after the initial supernova explosion, the interstellar debris cloud is faint at optical wavelengths. CTA 1's visible wavelength emission from still expanding shock fronts is revealed in this deep telescopic image , a frame that spans about 2 degrees across a starfield in the northern constellation of Cepheus. While no pulsar has since been found at radio wavelengths, in 2008 the Fermi Gamma-ray Space Telescope detected pulsed emission from CTA 1, identifying the supernova remnant's rotating neutron star. The source has been recognized as the first in a growing class of pulsars that are qui

In silhouette against a crowded star field along the tail of the arachnological constellation Scorpius , this dusty cosmic cloud evokes for some the image of an ominous dark tower. In fact, monstrous clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across this gorgeous telescopic portrait . A cometary globule , the swept-back cloud is shaped by intense ultraviolet radiation from the OB association of very hot stars in NGC 6231 , off the upper right corner of the scene. That energetic ultraviolet light also powers the globule's bordering reddish glow of hydrogen gas . Hot stars embedded in the dust can be seen as bluish reflection nebulae . This dark tower and associated nebulae are about 5,000 light-years away. from NASA https://ift.tt/EgUHGAj

Forget X-ray vision — imagine what you could see with gamma-ray vision! The featured all-sky map shows what the universe looks like to NASA's Fermi Gamma-ray Space Telescope . Fermi sees light with energies about a billion times what the human eye can see, and the map combines 12 years of Fermi observations. The colors represent the brightness of the gamma-ray sources , with brighter sources appearing lighter in color. The prominent stripe across the middle is the central plane of our Milky Way galaxy . Most of the red and yellow dots scattered above and below the Milky Way’s plane are very distant galaxies , while most of those within the plane are nearby pulsars . The blue background that fills the image is the diffuse glow of gamma-rays from distant sources that are too dim to be detected individually. Some gamma-ray sources remain unidentified and topics of research — currently no one knows what they are. from NASA https://ift.tt/oLVUQw8

A supermoon occurred yesterday. And tonight's moon should also look impressive. Supermoons appear slightly larger and brighter than most full moons because they reach their full phase when slightly nearer to the Earth -- closer than 90 percent of all full moons . This supermoon was also a blue moon given the definition that it is the third of four full moons occurring during a single season. Blue moons are not usually blue, and a different definition holds that a blue moon is the second full moon that occurs during a single month. The featured image captured the blue supermoon right near its peak size yesterday as it was rising beyond the Temple of Poseidon in Greece . This supermoon is particularly unusual in that it is the first of four successive supermoons, the next three occurring in September, October, and November. from NASA https://ift.tt/eiTORE1

Inside the Cocoon Nebula is a newly developing cluster of stars. Cataloged as IC 5146 , the beautiful nebula is nearly 15 light-year s wide. Soaring high in northern summer night skies , it's located some 4,000 light years away toward the constellation of the Swan ( Cygnus ). Like other star forming regions, it stands out in red, glowing, hydrogen gas excited by young, hot stars, and dust-reflected starlight at the edge of an otherwise invisible molecular cloud . In fact, the bright star found near the center of this nebula is likely only a few hundred thousand years old, powering the nebular glow as it clears out a cavity in the molecular cloud 's star forming dust and gas. A 48-hour long integration resulted in this exceptionally deep color view tracing tantalizing features within and surrounding the dusty stellar nursery . from NASA https://ift.tt/mH0ryvT

One of the most spectacular solar sights is an erupting prominence. In 2011, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressively large prominence erupting from the surface. The dramatic explosion was captured in ultraviolet light in the featured time lapse video covering 90 minutes, where a new frame was taken every 24 seconds. The scale of the prominence is huge -- the entire Earth would easily fit under the flowing curtain of hot gas. A solar prominence is channeled and sometimes held above the Sun's surface by the Sun's magnetic field . A quiescent prominence typically lasts about a month and may erupt in a Coronal Mass Ejection (CME) expelling hot gas into the Solar System . The energy mechanism that creates a solar prominence is a continuing topic of research . Our Sun is again near solar maximum and so very active, featuring numerous erupting prominences and CMEs, one of which resulted in picturesque auroras just over the past

On August 11 a Rocket Lab Electron rocket launched from a rotating planet. With a small satellite on board its mission was dubbed A Sky Full of SARs (Synthetic Aperture Radar satellites), departing for low Earth orbit from Mahia Peninsula on New Zealand's north island. The fiery trace of the Electron's graceful launch arc is toward the east in this southern sea and skyscape, a composite of 50 consecutive frames taken over 2.5 hours. Fixed to a tripod, the camera was pointing directly at the South Celestial Pole, the extension of planet Earth's axis of rotation in to space. But no bright star marks that location in the southern hemisphere's night sky. Still, the South Celestial Pole is easy to spot. It lies at the center of the concentric star trail arcs that fill the skyward field of view. from NASA https://ift.tt/0UaAtnF

A single exposure made with a camera pointed almost due north on August 12 recorded this bright Perseid meteor in the night sky west of Halifax, Nova Scotia , Canada. The meteor's incandescent trace is fleeting . It appears to cross the stars of the Big Dipper , famous northern asterism and celestial kitchen utensil, while shimmering curtains of aurora borealis, also known as the northern lights, dance in the night. Doubling the wow factor for night skywatchers near the peak of this year's Perseid meteor shower auroral activity on planet Earth was enhanced by geomagnetic storms . The intense space weather was triggered by flares from an active Sun . from NASA https://ift.tt/W5AI86U

Bright Mars and even brighter Jupiter are in close conjunction just above the pine trees in this post-midnight skyscape from Vallentuna , Sweden. Taken on August 12 during a geomagnetic storm, the snapshot records the glow of aurora borealis or northern lights, beaming from the left side of the frame. Of course on that date Perseid meteors rained through planet Earth's skies, grains of dust from the shower's parent, periodic comet Swift-Tuttle . The meteor streak at the upper right is a Perseid plowing through the atmosphere at about 60 kilometers per second . Also well-known in in Earth's night sky, the bright Pleides star cluster shines below the Perseid meteor streak. In Greek myth, the Pleiades were seven daughters of the astronomical titan Atlas and sea-nymph Pleione. The Pleiades and their parents' names are given to the cluster's nine brightest stars. from NASA https://ift.tt/vLVB1Ht

This was an unusual night. For one thing, the night sky of August 11 and 12, earlier this week, occurred near the peak of the annual Perseid Meteor Shower . Therefore, meteors streaked across the dark night as small bits cast off from Comet Swift-Tuttle came crashing into the Earth's atmosphere . Even more unusually, for central Germany at least, the night sky glowed purple . The red-blue hue was due to aurora caused by an explosion of particles from the Sun a few days before. This auroral storm was so intense that it was seen as far south as Texas and Italy , in Earth's northern hemisphere. The featured image composite was built from 7 exposures taken over 26 minutes from Ense , Germany . The Perseids occur predictably every August, but auroras visible this far south are more unusual and less predictable. from NASA https://ift.tt/NiS9EJI

What's that on the horizon? When circling the Earth on the International Space Station early last month , astronaut Matthew Dominick saw an unusual type of lightning just beyond the Earth's edge: a gigantic jet. The powerful jet appears on the left of the featured image in red and blue. Giant jet lightning has only been known about for the past 23 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 remains an active topic of research . from NASA https://ift.tt/2VTWywN

What's happening in the sky above Stonehenge? A meteor shower: specifically, the Perseid meteor shower . A few nights ago, after the sky darkened , many images of meteors from this year's Perseids were captured separately and merged into a single frame. 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 vertical through the image center. The featured image was taken from Wiltshire , England , being careful to include, at the bottom, the famous astronomical monument of Stonehenge . Although the Perseids peaked last night, some Perseid meteors should still be visible for a few more nights. from NASA ht

Messier 20 , popularly known as the Trifid Nebula, lies about 5,000 light-years away toward the nebula rich constellation Sagittarius. A star forming region in the plane of our galaxy, the Trifid does illustrate three different types of astronomical nebulae; red emission nebulae dominated by light from hydrogen atoms, blue reflection nebulae produced by dust reflecting starlight, and dark nebulae where dense dust clouds appear in silhouette. The reddish emission region, roughly separated into three parts by obscuring dust lanes, is what lends the Trifid its popular name . The cosmic cloud complex is over 40 light-years across and would cover the area of a full moon on planet Earth's sky. But the Trifid Nebula is too faint to be seen by the unaided eye. Over 75 hours of image data captured under dark night skies was used to create this stunning telescopic view . from NASA https://ift.tt/K0s9weD

Denizens of planet Earth typically watch meteor showers by looking up . But this remarkable view , captured on August 13, 2011 by astronaut Ron Garan, caught a Perseid meteor by looking down. From Garan's perspective on board the International Space Station orbiting at an altitude of about 380 kilometers, the Perseid meteors streak below, swept up dust from comet Swift-Tuttle . The vaporizing comet dust grains are traveling at about 60 kilometers per second through the denser atmosphere around 100 kilometers above Earth's surface. In this case, the foreshortened meteor flash is near frame center, below the curving limb of the Earth and a layer of greenish airglow, just below bright star Arcturus . Want to look up at a meteor shower? You're in luck , as the 2024 Perseid meteor shower is active now and predicted to peak near August 12. With interfering bright moonlight absent, this year you'll likely see many Perseid meteors under clear, dark skies after midnight. f

A Halley-type comet with an orbital period of about 133 years, Comet 109P/Swift-Tuttle is recognized as the parent of the annual Perseid Meteor Shower. The comet's last visit to the inner Solar System was in 1992 . Then, it did not become easily visible to the naked eye, but it did become bright enough to see from most locations with binoculars and small telescopes. This stunning color image of Swift-Tuttle's greenish coma, long ion tail and dust tail was recorded using film on November 24, 1992 . That was about 16 days after the large periodic comet's closest approach to Earth. Comet Swift-Tuttle is expected to next make an impressive appearance in night skies in 2126. Meanwhile, dusty cometary debris left along the orbit of Swift-Tuttle will continue to be swept up creating planet Earth's best-known July and August meteor shower . from NASA https://ift.tt/LEz0j1v

To some, they look like battlements, here protecting us against the center of the Milky Way . The Three Merlon s, also called the Three Peaks of Lavaredo , stand tall today because they are made of dense dolomite rock which has better resisted erosion than surrounding softer rock. They formed about 250 million years ago and so are comparable in age with one of the great extinctions of life on Earth . A leading hypothesis is that this great extinction was triggered by an asteroid about 10-km across, larger in size than Mount Everest , impacting the Earth. Humans have gazed up at the stars in the Milky Way and beyond for centuries, making these battlefield-like formations, based in the Sexten Dolomites , a popular place for current and ancient astronomers . from NASA https://ift.tt/eZroCLk

What makes this storm cloud so colorful? First, the cloud itself is composed of millions of tiny droplets of water and ice. Its bottom is almost completely flat -- but this isn't unusual. Bottom flatness in clouds is generally caused by air temperature dropping as you go up, and that above a specific height, water-saturated air condenses out water droplets. The shape of the cloud middle is caused by a water-droplet-laden column of air being blown upward. Most unusual , though, are the orange and yellow colors. Both colors are caused by the cloud's water drops reflecting sunlight. The orange color in the cloud's middle and bottom sections are reflections of a nearly red sunset . In contrast, the yellow color of the cloud's top results from reflection of light from a not-yet-setting Sun , where some -- but less -- blue light is being scattered away . Appearing to float above the plains in Texas , the featured impressive image of a dynamic cumulonimbus cloud was c

That's no moon . On the ground, that's the Lars Homestead in Tunisia . And that's not just any galaxy. That's the central band of our own Milky Way galaxy . Last, that's not just any meteor. It is a bright fireball likely from last year's Perseids meteor shower . The featured image composite combines consecutive exposures taken by the same camera from the same location. This year's Perseids peak during the coming weekend is expected to show the most meteors after the first quarter moon sets, near midnight. To best experience a meteor shower, you should have clear and dark skies, a comfortable seat , and patience. from NASA https://ift.tt/jMLqpAX

What would it look like to return home from outside our galaxy? Although designed to answer greater questions , data from ESA's robotic Gaia mission is helping to provide a uniquely modern perspective on humanity's place in the universe. Gaia orbits the Sun near the Earth and resolves stars' positions so precisely that it can determine a slight shift from its changing vantage point over the course of a year, a shift that is proportionately smaller for more distant stars -- and so determines distance . In the first sequence of the video , an illustration of the Milky Way is shown that soon resolves into a three-dimensional visualization of Gaia star data . A few notable stars are labelled with their common names , while others stars are labelled with numbers from a Gaia catalog . Eventually, the viewer arrives in our stellar neighborhood where many stars were tracked by Gaia, and soon at our home star Sol, the Sun . At the video's end, the reflective glow of

On a road trip up Mount Uludağ in Bursa province, Turkey these motorcyclists found themselves above low clouds and fog in late June. With the bright Sun directly behind them, the view down the side of the great mountain revealed a beautiful, atmospheric glory and fog bow. Known to some as the heiligenschein or the Specter of the Brocken , a glory can also sometimes be seen from airplanes or even high buildings. It often appears to be a dark giant surrounded by a bright halo. Of course the dark giant is just the shadow of the observer (90MB video) cast opposite the Sun. The clouds and fog are composed of very small water droplets, smaller than rain drops, that refract and reflect sunlight to create the glory's colorful halo and this more extensive fog bow. from NASA https://ift.tt/bSsPwB2

As Mars wanders through Earth's night, it passes about 5 degrees south of the Pleiades star cluster in this composite astrophoto. The skyview was constructed from a series of images captured over a run of 16 consecutive clear nights beginning on July 12. Mars' march across the field of view begins at the far right, the planet's ruddy hue. showing a nice contrast with the blue Pleiades stars. Moving much faster across the sky against the distant stars, the fourth planet from the Sun easily passes seventh planet Uranus, also moving across this field of view. Red planet Mars and the ice giant world were in close conjunction, about 1/2 degree apart, on July 16. Continuing its rapid eastward trek, Mars has now left the sister stars and outer planet behind though, passing north of red giant star Aldebaran. Mars will come within about 1/3 degree of Jupiter in planet Earth's sky on August 14. from NASA https://ift.tt/YyOl5ri

A visitor to the inner solar system every 70 years or so Comet 13P/Olbers reached its most recent perihelion, or closest approach to the Sun, on June 30 2024. Now on a return voyage to the distant Oort cloud the Halley-type comet is recorded here sweeping through northern summer night skies over historic Kunetice Castle , Czech Republic. Along with a broad dust tail, and brighter coma, this comet's long ion tail buffeted by storms and winds from the Sun, is revealed in the composite of tracked exposures for comet and sky, and fixed exposures for foreground landscape recorded on July 28. The comet is about 16 light-minutes beyond the castle and seen against faint background stars below the northern constellation Ursa Major. The hilltop castle dates to the 15th century, while Heinrich Olbers discovered the comet in 1815. Captured here low in northwestern skies just after sunset Comet Olbers, for now, offers skywatchers on planet Earth rewarding telescopic and binocular views.

What is creating these unusual spots? Light-colored spots on Martian rocks , each surrounded by a dark border, were discovered earlier this month 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 ring, like some similarly appearing spots on Earth rocks . Although other non-biological explanations may ultimately prevail, speculation focusing on this potential biological origin is causing much intrigue . from NASA https://ift.tt/vsZAueI

To some, it looks like a penguin. But to people who study the universe, it is an interesting example of two big galaxies interacting. Just a few hundred million years ago, the upper NGC 2936 was likely a normal spiral galaxy : spinning, creating stars, and minding its own business. Then it got too close to the massive elliptical galaxy NGC 2937, below, and took a dive. Together known as Arp 142 , they are featured in this new Webb infrared image, while a visible light Hubble image appears in comparison. NGC 2936 is not only being deflected, but distorted , by this close gravitational interaction. When massive galaxies pass near each other, gas is typically condensed from which new stars form . A young group of stars appears as the nose of the penguin toward the right of the upper galaxy, while in the center of the spiral , bright stars together appear as an eye. Before a billion years, the two galaxies will likely merge into one larger galaxy. from NASA https://ift.tt/1BsJ6g

What's happening above Uluru? A United Nations World Heritage Site , Uluru is an extraordinary 350-meter high mountain in central Australia that rises sharply from nearly flat surroundings. Composed of sandstone , Uluru has slowly formed over the past 300 million years as softer rock eroded away. The Uluru region has been a home to humans for over 22,000 years. Recorded last month, the starry sky above Uluru includes the central band of our Milky Way galaxy , complete with complex dark filaments of dust , bright red emission nebulas , and billions of stars. from NASA https://ift.tt/usjH1QB

Sometimes, the surface of our Sun seems to dance. In the middle of 2012, for example, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence that seemed to perform a running dive roll like an acrobatic dancer. The dramatic explosion was captured in ultraviolet light in the featured time-lapse video covering about three hours. A looping magnetic field directed the flow of hot plasma on the Sun . The scale of the dancing prominence is huge -- the entire Earth would easily fit under the flowing arch of hot gas. A quiescent prominence typically lasts about a month and may erupt in a Coronal Mass Ejection (CME), expelling hot gas into the Solar System . The energy mechanism that creates a solar prominence is still a topic of research . Like in 2012, this year the Sun's surface is again quite active and features many filaments and prominences . from NASA https://ift.tt/71wJXVy