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The monsters that live on the Sun are not like us. They are larger than the Earth and made of gas hotter than in any teapot . They have no eyes, but at times, many tentacles . They float . Usually, they slowly change shape and just fade back onto the Sun over about a month. Sometimes, though, they suddenly explode and unleash energetic particles into the Solar System that can attack the Earth.  Pictured is a huge solar prominence imaged almost two weeks ago in the light of hydrogen . Captured by a small telescope in Gilbert , Arizona , USA , the monster esque plume of gas was held aloft by the ever-present but ever-changing magnetic field near the surface of the Sun. Our active Sun continues to show an unusually high number of prominences , filaments , sunspots , and large active regions  as solar maximum approaches in 2025. from NASA https://ift.tt/my2pj1i

Why is Phobos so dark? Phobos , the largest and innermost of the two Martian moons, is the darkest moon in the entire Solar System . Its unusual orbit and color indicate that it may be a captured asteroid composed of a mixture of ice and dark rock. The featured assigned-color picture of Phobos near the edge of Mars was captured in late 2021 by ESA 's robot spacecraft Mars Express , currently orbiting Mars. Phobos is a heavily cratered and barren moon, with its largest crater located on the far side. From images like this, Phobos has been determined to be covered by perhaps a meter of loose dust . Phobos orbits so close to Mars that from some places it would appear to rise and set twice a day, while from other places it would not be visible at all. Phobos ' orbit around Mars is continually decaying -- it will likely break up with pieces crashing to the Martian surface in about 50 million years. from NASA https://ift.tt/uYmNe5n

Admire the beauty but fear the beast. The beauty is the aurora overhead , here taking the form of a great green spiral , seen between picturesque clouds with the bright Moon to the side and stars in the background. The beast is the wave of charged particles that creates the aurora but might, one day, impair civilization. In 1859, following notable auroras seen all across the globe, a pulse of charged particles from a coronal mass ejection (CME) associated with a solar flare impacted Earth's magnetosphere so forcefully that it created the Carrington Event . This assault from the Sun compressed the Earth's magnetic field so violently that it created high currents and sparks along telegraph wires, shocking many telegraph operators . Were a Carrington-class event to impact the Earth today, speculation holds that damage might occur to global power grids and electronics on a scale never yet experienced. The featured aurora was imaged in 2016 over Thingvallavatn Lake in I...

Bright sunlight glints as long dark shadows mark this image of the surface of the Moon . It was taken fifty-four years ago, July 20, 1969, by Apollo 11 astronaut Neil Armstrong , the first to walk on the lunar surface. Pictured is the mission's lunar module, the Eagle, and spacesuited lunar module pilot Buzz Aldrin. Aldrin is unfurling a long sheet of foil also known as the Solar Wind Composition Experiment . Exposed facing the Sun, the foil trapped particles streaming outward in the solar wind, catching a sample of material from the Sun itself. Along with moon rocks and lunar soil samples, the solar wind collector was returned for analysis in earthbound laboratories. from NASA https://ift.tt/DuG4Vrd

High-speed outflows of molecular gas from a pair of actively forming young stars shine in infrared light, revealing themselves in this NIRcam image from the James Webb Space Telescope. Cataloged as HH (Herbig-Haro) 46/47, the young stars are lodged within a dark nebula that is largely opaque when viewed in visible light. The pair lie at the center of the prominent reddish diffraction spikes in the NIRcam image. Their energetic stellar jets extend for nearly a light-year, burrowing into the dark interstellar material. A tantalizing object to explore with Webb's infrared capabilities, this young star system is relatively nearby, located only some 1,140 light-years distant in the nautical constellation Vela . from NASA https://ift.tt/CZmpyFc

Large galaxies grow by eating small ones. Even our own galaxy engages in a sort of galactic cannibalism , absorbing small galaxies that are too close and are captured by the Milky Way's gravity. In fact, the practice is common in the universe and illustrated by this striking pair of interacting galaxies from the banks of the southern constellation Eridanus , The River . Located over 50 million light years away, the large, distorted spiral NGC 1532 is seen locked in a gravitational struggle with dwarf galaxy NGC 1531, a struggle the smaller galaxy will eventually lose . Seen nearly edge-on, spiral NGC 1532 spans about 100,000 light-years. The merging galaxies are captured in this sharp image from the Dark Energy Camera mounted on the National Science Foundation’s Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile. The NGC 1532/1531 pair is thought to be similar to the well-studied system of face-on spiral and small companion known as M51 . from NAS...

South of Antares , in the tail of the nebula-rich constellation Scorpius , lies emission nebula IC 4628. Nearby hot, massive stars , millions of years young, irradiate the nebula with invisible ultraviolet light, stripping electrons from atoms. The electrons eventually recombine with the atoms to produce the visible nebular glow, dominated by the red emission of hydrogen. At an estimated distance of 6,000 light-years, the region shown is about 250 light-year s across, spanning over three full moons on the sky . The nebula is also cataloged as Gum 56 for Australian astronomer Colin Stanley Gum , but seafood-loving deep sky-enthusiasts might know this cosmic cloud as the Prawn Nebula . The graceful color image is a new astronomical composition taken over several nights in April from Rio Hurtado , Chile . from NASA https://ift.tt/hL6XqAf

What do the famous Eagle Nebula star pillars look like in X-ray light? To find out, NASA's orbiting Chandra X-ray Observatory peered in and through these interstellar mountains of star formation. It was found that in M16 the dust pillars themselves do not emit many X-rays , but a lot of small-but-bright X-ray sources became evident. These sources are shown as bright dots on the featured image which is a composite of exposures from Chandra ( X-rays ), XMM (X-rays), JWST ( infrared ), Spitzer (infrared), Hubble ( visible ), and the VLT (visible). What stars produce these X-rays remains a topic of research , but some are hypothesized to be hot, recently-formed, low-mass stars , while others are thought to be hot, older, high-mass stars. These X-ray hot stars are scattered around the frame -- the previously identified Evaporating Gaseous Globules (EGGS) seen in visible light are not currently hot enough to emit X-rays. from NASA https://ift.tt/v7WFYzn

Meteors can be colorful. While the human eye usually cannot discern many colors, cameras often can. Pictured here is a fireball , a disintegrating meteor that was not only one of the brightest the photographer has ever seen , but colorful. The meteor was captured by chance in mid-July with a camera set up on Hochkar Mountain in Austria to photograph the central band of our Milky Way galaxy . The radiant grit , likely cast off by a comet or asteroid long ago, had the misfortune to enter Earth's atmosphere . Colors in meteors usually originate from ionized chemical elements released as the meteor disintegrates, with blue-green typically originating from magnesium , calcium radiating violet, and nickel glowing green. Red, however, typically originates from energized nitrogen and oxygen in the Earth's atmosphere. This bright meteor ic fireball was gone in a flash -- less than a second -- but it left a wind-blown ionization trail that remained visible for almost a min...

It does what? No one knew that 2,000 years ago, the technology existed to build such a device. The Antikythera mechanism , pictured, is now widely regarded as the first computer . Found at the bottom of the sea aboard a decaying Greek ship, its complexity prompted decades of study, and even today some of its functions likely remain unknown . X-ray images of the device, however, have confirmed that a main function of its numerous clock-like wheels and gears is to create a portable, hand-cranked, Earth-centered, orrery of the sky , predicting future star and planet locations as well as lunar and solar eclipse s. The corroded core of the Antikythera mechanism 's largest gear is featured, spanning about 13 centimeters, while the entire mechanism was 33 centimeters high, making it similar in size to a large book. Recently, modern computer modeling of missing components is allowing for the creation of a more complete replica of this surprising ancient machine . from NASA https:...

A photograph of Buzz Aldrin standing on the Moon taken by Neil Armstrong , was digitally reversed to create this lunar selfie. Captured in July 1969 following the Apollo 11 moon landing, Armstrong's original photograph recorded not only the magnificent desolation of an unfamiliar world , but Armstrong himself reflected in Aldrin's curved visor. In the unwrapped image , the spherical distortion of the reflection in Aldrin's helmet has been reversed. The transformed view features Armstrong himself from Aldrin's perspective . Since Armstrong took the original picture, today the image represents a fifty-four year old lunar selfie. Aldrin's visor reflection in the original image appears here on the left. Bright (but distorted) planet Earth hangs in the lunar sky above Armstrong's figure, toward the upper right. A foil-wrapped leg of the Eagle lander and Aldrin's long shadow stretching across the lunar surface are prominently visible. In 2024 NASA's Ar...

The combined light of stars along the Milky Way are reflected by these cosmic dust clouds that soar 300 light-years or so above the plane of our galaxy. Known to some as integrated flux nebulae and commonly found at high galactic latitudes, the dusty galactic cirrus clouds are faint. But they can be traced over large regions of the sky toward the North and South Galactic poles. Along with the reflection of starlight, studies indicate the dust clouds produce a faint reddish luminescence as interstellar dust grains convert invisible ultraviolet radiation to visible red light. Also capturing nearby Milky Way stars and distant background galaxies, this remarkably deep, wide-field image explores a complex of faint galactic cirrus known as Mandel Wilson 9. It spans over three degrees across planet Earth's skies toward the far southern constellation Apus. from NASA https://ift.tt/pG02Int

This magnificent spiral galaxy is Messier 64 , often called the Black Eye Galaxy or the Sleeping Beauty Galaxy for its dark-lidded appearance in telescopic views. The spiral's central region, about 7,400 light-years across, is pictured in this reprocessed image from the Hubble Space Telescope. M64 lies some 17 million light-years distant in the otherwise well-groomed northern constellation Coma Berenices . The enormous dust clouds partially obscuring M64's central region are laced with young, blue star clusters and the reddish glow of hydrogen associated with star forming regions. But imposing clouds of dust are not this galaxy's only peculiar feature. Observations show that M64 is actually composed of two concentric, counter-rotating systems. While all the stars in M64 rotate in the same direction as the interstellar gas in the galaxy's central region, gas in the outer regions, extending to about 40,000 light-years, rotates in the opposite direction. The dusty eye ...

Birds don't fly this high. Airplanes don't go this fast. The Statue of Liberty weighs less. No species other than human can even comprehend what is going on , nor could any human just a millennium ago . The launch of a rocket bound for space is an event that inspires awe and challenges description. Pictured here last week, the Indian Space Research Organization 's LVM3 rocket blasted off from the Satish Dhawan Space Centre on Sriharikota Island, India . From a standing start, the 600,000+ kilogram rocket ship lifted the massive Chandrayaan-3 off the Earth. The Chandrayaan-3 mission is scheduled to reach the Moon in late August and land a robotic rover near the lunar South Pole . Rockets bound for space are now launched from somewhere on Earth every few days . from NASA https://ift.tt/dN9rXL4

What's happening in the night sky? To help find out, telescopes all over the globe will be pointing into deep space. Investigations will include trying to understand the early universe , finding and tracking Earth-menacing asteroids , searching for planets that might contain extra-terrestrial life , and monitoring stars to help better understand our Sun. The featured composite includes foreground and background images taken in April from a mountaintop on La Palma island in the Canary Islands of Spain . Pictured, several telescopes from the Roque de los Muchachos Observatory are shown in front of a dark night sky. Telescopes in the foreground include, left to right, Magic 1, Galileo , Magic 2, Gran Canarian , and LST . Sky highlights in the background include the central band of our Milky Way Galaxy , the constellations of Sagittarius , Ophiuchus and Scorpius , the red-glowing Eagle and Lagoon Nebulas , and the stars Alrami and Antares . Due to observatories like this...

What's happening around this star? No one is sure. CW Leonis is the closest carbon star , a star that appears orange because of atmospheric carbon dispersed from interior nuclear fusion . But CW Leonis also appears engulfed in a gaseous carbon-rich nebula. What causes the nebula's complexity is unknown , but its geometry of shells and arcs are surely intriguing . The featured image by the Hubble Space Telescope details this complexity. The low surface gravity of carbon stars enhances their ability to expel carbon and carbon compounds into space. Some of this carbon ends up forming dark dust that is commonly seen in the nebulas of young star-forming regions and the disks of galaxies . Humans and all Earth-based life are carbon-based , and at least some of our carbon was likely once circulating in the atmospheres of near-death stars like carbon stars . from NASA https://ift.tt/YyIT5EP

Now this was a view with a thrill. From Mount Tschirgant in the Alps , you can see not only nearby towns and distant Tyrol ean peaks, but also, weather permitting, stars, nebulas, and the band of the Milky Way Galaxy . What made the arduous climb worthwhile this night, though, was another peak -- the peak of the 2018 Perseids Meteor Shower . As hoped, dispersing clouds allowed a picturesque sky-gazing session that included many faint meteors , all while a carefully positioned camera took a series of exposures. Suddenly, a thrilling meteor -- bright and colorful -- slashed down right next to the nearly vertical band of the Milky Way . As luck would have it, the camera caught it too. Therefore, a new image in the series was quickly taken with one of the sky-gazers posing on the nearby peak. Later, all of the images were digitally combined . from NASA https://ift.tt/Tj3HKYy

This stunning infrared image was released one year ago as the James Webb Space Telescope began its exploration of the cosmos. The view of the early Universe toward the southern constellation Volans was achieved in 12.5 hours of exposure with Webb's NIRCam instrument. Of course the stars with six spikes are well within our own Milky Way. Their diffraction pattern is characteristic of Webb's 18 hexagonal mirror segments operating together as a single 6.5 meter diameter primary mirror. The thousands of galaxies flooding the field of view are members of the distant galaxy cluster SMACS0723-73, some 4.6 billion light-years away. Luminous arcs that seem to infest the deep field are even more distant galaxies though. Their images are distorted and magnified by the dark matter dominated mass of the galaxy cluster, an effect known as gravitational lensing. Analyzing light from two separate arcs below the bright spiky star, Webb's NIRISS instrument indicates the arcs are both...

Comet C/2023 E1 (ATLAS) was just spotted in March, another comet found by the NASA funded Asteroid Terrestrial-impact Last Alert System. On July 1 this Comet ATLAS reached perihelion, its closest approach to the Sun. Shortly afterwards the telescopic comet was captured in this frame sporting a pretty greenish coma and faint, narrow ion tail against a background of stars in the far northern constellation Ursa Minor. This comet's closest approach to Earth is still to come though. On August 18 this visitor to the inner Solar System will be a mere 3 light-minutes or so from our fair planet. Based on its inclination to the ecliptic plane and orbital period of about 85 years C/2023 E1 (ATLAS) is considered a Halley-type comet . from NASA https://ift.tt/o1TQCqu

A mere 390 light-years away , Sun-like stars and future planetary systems are forming in the Rho Ophiuchi molecular cloud complex, the closest star-forming region to our fair planet. The James Webb Space Telescope's NIRCam peered into the nearby natal chaos to capture this infrared image at an inspiring scale . The spectacular cosmic snapshot was released to celebrate the successful first year of Webb's exploration of the Universe. The frame spans less than a light-year across the Rho Ophiuchi region and contains about 50 young stars. Brighter stars clearly sport Webb's characteristic pattern of diffraction spikes . Huge jets of shocked molecular hydrogen blasting from newborn stars are red in the image, with the large, yellowish dusty cavity carved out by the energetic young star near its center. Near some stars in the stunning image are shadows cast by their protoplanetary disks . from NASA https://ift.tt/aEPtgLw

Why do some spiral galaxies have a ring around the center? Spiral galaxy NGC 1398 not only has a ring of pearly stars, gas and dust around its center, but a bar of stars and gas across its center, and spiral arms that appear like ribbons farther out. The featured deep image from Observatorio El Sauce in Chile shows the grand spiral galaxy in impressive detail. NGC 1398 lies about 65 million light years distant, meaning the light we see today left this galaxy when dinosaurs were disappearing from the Earth . The photogenic galaxy is visible with a small telescope toward the constellation of the Furnace ( Fornax ). The ring near the center is likely an expanding density wave of star formation, caused either by a gravitational encounter with another galaxy , or by the galaxy's own gravitational asymmetries . from NASA https://ift.tt/kV7WCFn

Why is our Sun so active now ? No one is sure. An increase in surface activity was expected because our Sun is approaching solar maximum in 2025. However, last month our Sun sprouted more sunspot s than in any month during the entire previous 11-year solar cycle -- and even dating back to 2002. The featured picture is a composite of images taken every day from January to June by NASA 's Solar Dynamic Observatory . Showing a high abundance of sunspots, large individual spots can be tracked across the Sun's disk, left to right, over about two weeks. As a solar cycle continues, sunspots typically appear closer to the equator. Sunspots are just one way that our Sun displays surface activity -- another is flares and coronal mass ejections (CMEs) that expel particles out into the Solar System . Since these particles can affect astronauts and electronics, tracking surface disturbances is of more than aesthetic value . Conversely, solar activity can have very high aesthetic v...

When stars form, pandemonium reigns. A textbook case is the star forming region NGC 6559 . Visible in the featured image are red glowing emission nebula s of hydrogen , blue reflection nebulas of dust , dark absorption nebulas of dust, and the stars that formed from them. The first massive stars formed from the dense gas will emit energetic light and winds that erode, fragment, and sculpt their birthplace. And then they explode . The resulting morass can be as beautiful as it is complex . After tens of millions of years, the dust boils away, the gas gets swept away, and all that is left is a bare open cluster of stars. from NASA https://ift.tt/UlrIkj9

Eta Carinae may be about to explode. But no one knows when - it may be next year, it may be one million years from now. Eta Carinae 's mass - about 100 times greater than our Sun - makes it an excellent candidate for a full blown supernova . Historical records do show that about 170 years ago Eta Carinae underwent an unusual outburst that made it one of the brightest stars in the southern sky . Eta Carinae , in the Keyhole Nebula , is the only star currently thought to emit natural LASER light . This featured image brings out details in the unusual nebula that surrounds this rogue star . Diffraction spikes , caused by the telescope, are visible as bright multi-colored streaks emanating from Eta Carinae's center. Two distinct lobes of the Homunculus Nebula encompass the hot central region , while some strange radial streaks are visible in red extending toward the image right. The lobes are filled with lanes of gas and dust which absorb the blue and ultraviolet light e...

Stickney Crater, the largest crater on the martian moon Phobos, is named for Chloe Angeline Stickney Hall, mathematician and wife of astronomer Asaph Hall. Asaph Hall discovered both the Red Planet's moons in 1877. Over 9 kilometers across, Stickney is nearly half the diameter of Phobos itself, so large that the impact that blasted out the crater likely came close to shattering the tiny moon. This enhanced-color image of Stickney and surroundings was recorded by the HiRISE camera onboard the Mars Reconnaissance Orbiter as it passed within some six thousand kilometers of Phobos in March of 2008. Even though the surface gravity of asteroid-like Phobos is less than 1/1000th Earth's gravity, streaks suggest loose material slid down inside the crater walls over time. Light bluish regions near the crater's rim could indicate a relatively freshly exposed surface. The origin of the curious grooves along the surface is mysterious but may be related to tidal stresses experienc...

This pretty 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 (top) 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 they were likely a product of the same star-forming region. Always a rewarding sight in binoculars , the Double Cluster is even visible to the unaided eye from dark locations . from NASA https://ift.tt/4wrt9Az

On July 4, an almost Full Moon rose in planet Earth's evening skies. Also known as a Buck Moon, the full lunar phase ( full on July 3 at 11:39 UTC) was near perigee, the closest point in the Moon's almost monthly orbit around planet Earth. That qualified this July's Full Moon as a supermoon, the first of four supermoons in 2023 . Seen from Cocoa Beach along Florida's Space Coast on July 4, any big, bright, beautiful Full Moon would still have to compete for attention though. July's super-moonrise was captured here against a super-colorful fireworks display. from NASA https://ift.tt/Rt9Ndoz

What if you could see out to the edge of the observable universe ? You would see galaxies, galaxies, galaxies, and then, well, quasar s, which are the bright centers of distant galaxies . To expand understanding of the very largest scales that humanity can see, a map of the galaxies and quasars found by the Sloan Digital Sky Survey from 2000 to 2020 -- out to near the edge of the observable universe -- has been composed. Featured here , one wedge from this survey encompasses about 200,000 galaxies and quasars out beyond a look-back time of 12 billion years and cosmological redshift 5. Almost every dot in the nearby lower part of the illustration represents a galaxy , with redness indicating increasing redshift and distance. Similarly, almost every dot on the upper part represents a distant quasar , with blue-shaded dots being closer than red. Clearly shown among many discoveries , gravity between galaxies has caused the nearby universe to condense and become increasingly m...

It seemed like the sky exploded. The original idea was to photograph an aurora over a waterfall. After waiting for hours under opaque clouds , though, hope was running out. Others left. Then, unexpectedly, the clouds moved away. Suddenly, particles from a large solar magnetic storm were visible impacting the Earth's upper atmosphere with full effect. The night sky filled with colors and motion in a thrilling auroral display. Struggling to steady the camera from high Earthly winds , the 34 exposures that compose the featured image were taken. The resulting featured composite image shows the photogenic Godafoss (Goðafoss) waterfall in northern Iceland in front of a very active aurora in late February. The solar surface explosion that expelled the energetic particles occurred a few days before . Our Sun is showing an impressive amount of surface activity as it approaches solar maximum , indicating that more impressive auroras are likely to appear in Earth's northern an...

Why is Venus so different from Earth? To help find out, Japan launched the robotic Akatsuki spacecraft which entered orbit around Venus late in 2015 after an unplanned five-year adventure around the inner Solar System . Even though Akatsuki was past its original planned lifetime, the spacecraft and instruments were operating so well that much of its original mission was reinstated . Also known as the Venus Climate Orbiter, Akatsuki's instruments investigated unknowns about Earth's sister planet, including whether volcanoes are still active, whether lightning occurs in the dense atmosphere, and why wind speeds greatly exceed the planet's rotation speed. In the featured image taken by Akatsuki 's UVI camera, the day-side of Venus is seen shown with planet-scale V-shaped cloud pattern. The image displays three ultraviolet colors and indicates a dip in the relative abundance of sulfur dioxide shown in faint blue. Analyses of Akatsuki images and data has show...

It was one of the better skies of this long night. In parts of Antarctica , not only is it winter, but the Sun can spend weeks below the horizon. At China 's Zhongshan Station , people sometimes venture out into the cold to photograph a spectacular night sky. The featured image from one such outing was taken in mid-July of 2015, just before the end of this polar night . Pointing up, the wide angle lens captured not only the ground at the bottom, but at the top as well. In the foreground, a colleague is taking pictures. In the distance, a spherical satellite receiver and several windmills are visible. Numerous stars dot the night sky, including Sirius and Canopus . Far in the background, stretching overhead from horizon to horizon, is the central band of our Milky Way Galaxy . Even further in the distance, visible as extended smudges near the top, are the Large and Small Magellanic Clouds , satellite galaxies near our huge Milky Way Galaxy . from NASA https://ift.tt/1bIAP...

This tantalizing trio of galaxies sometimes called the Draco Group, is located in the northern constellation of (you guessed it) Draco, the Dragon . From left to right are face-on spiral NGC 5985, elliptical galaxy NGC 5982, and edge-on spiral NGC 5981, all found within this single telescopic field of view that spans a little more than the width of the full moon. While the group is far too small to be a galaxy cluster , and has not been catalogued as a compact galaxy group, the three galaxies all do lie roughly 100 million light-years from planet Earth. Not as well known as other tight groupings of galaxies , the contrast in visual appearance still makes this triplet an attractive subject for astroimagers. On close examination with spectrographs , the bright core of striking spiral NGC 5985 shows prominent emission in specific wavelengths of light, prompting astronomers to classify it as a Seyfert , a type of active galaxy. This impressively deep exposure hints at a faint dim hal...

Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction event s have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth . Pictured here are the orbits of the over 1,000 known Potentially Hazardous Asteroids (PHAs). These documented tumbling boulders of rock and ice are over 140 meters across and will pass within 7.5 million kilometers of Earth -- about 20 times the distance to the Moon. Although none of them will strike the Earth in the next 100 years -- not all PHAs have been discovered , and past 100 years, many orbits become hard to predict. Were an asteroid of this size to impact the Earth , it could raise dangerous tsunami s, for example. To investigate Earth-saving strategies, NASA successfully tested the Double Asteroid Redirection Test ( DART ) mission last year. Of cours...

Monitoring 68 pulsar s with very large radio telescope s, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has uncovered evidence for the gravitational wave (GW) background by carefully measuring slight shifts in the arrival times of pulses. These shifts are correlated between different pulsar s in a way that indicates that they are caused by GWs. This GW background is likely due to hundreds of thousands or even millions of supermassive black hole binaries . Teams in Europe , Asia and Australia have also independently reported their results today. Previously, the LIGO and Virgo detectors have detected higher-frequency GWs from the merging of individual pairs of massive orbiting objects , such as stellar-mass black holes . The featured illustration highlights this spacetime -shaking result by depicting two orbiting supermassive black holes and several of the pulsars that would appear to have slight timing shifts. The imprint these GWs make on s...

Unlike most entries in Charles Messier's famous catalog of deep sky objects, M24 is not a bright galaxy, star cluster, or nebula. It's a gap in nearby, obscuring interstellar dust clouds that allows a view of the distant stars in the Sagittarius spiral arm of our Milky Way galaxy. Direct your gaze through this gap with binoculars or small telescope and you are looking through a window over 300 light-years wide at stars some 10,000 light-years or more from Earth. Sometimes called the Small Sagittarius Star Cloud, M24's luminous stars fill this gorgeous starscape . Covering over 3 degrees or the width of 6 full moons in the constellation Sagittarius, the telescopic field of view includes dark markings B92 and B93 near center , along with other clouds of dust and glowing nebulae toward the center of the Milky Way. from NASA https://ift.tt/ZKgqaAr

These two global views of Mars were captured at ultraviolet wavelengths, beyond the spectrum visible to human eyes. Recorded by the MAVEN spacecraft's Imaging Ultraviolet Spectrograph instrument in July 2022 (left) and January 2023, three otherwise invisible ultraviolet bands are mapped into red, green, and blue colors. That color scheme presents the Red Planet's surface features in shades of tan and green. Haze and clouds appear white or blue, while high altitude ozone takes on a dramatic purple hue. On the left, Mars' south polar ice cap is in brilliant white at the bottom but shrinking during the southern hemisphere's summer season . On the right, the northern hemisphere's polar region is seen shrouded in clouds and atmospheric ozone. Known to some as the Mars Atmosphere and Volatile EvolutioN spacecraft, MAVEN has been exploring Mars' tenuous upper atmosphere, ionosphere, and its interactions with the Sun and solar wind since 2014 . from NASA https://...

You've surely seen it, but you might not have noticed it. During a cloudless twilight , just before sunrise or after sunset , part of the atmosphere above the horizon appears slightly dark and off-color. Called the Belt of Venus , this transitional band between the dark eclipsed sky and the bright day sky can be seen most prominently in the direction opposite the Sun . Straight above, blue sky is normal sunlight reflecting off the atmosphere, while near the horizon the clear sky can appear more orange or red . In the Belt of Venus , the atmosphere reflects more light from the setting (or rising) Sun and so appears more red . Featured here, the Belt of Venus was photographed over several Himalayan mountains including, second from the right, Mount Everest , the tallest mountain on Earth . Although usually not mentioned , the belt is frequently caught by accident in other photographs . from NASA https://ift.tt/mVU6f1i

Does lightning occur only on Earth? No. Spacecraft in our Solar System have detected lightning on other planets, including Mars , Jupiter and Saturn , and lightning is likely on Venus , Uranus, and Neptune . Lightning is a sudden rush of electrically charged particles from one location to another. On Earth , drafts of colliding ice and water droplets usually create lightning-generating charge separation, but what happens on Jupiter ? Images and data from NASA's Jupiter-orbiting Juno spacecraft bolster previous speculation that Jovian lightning is also created in clouds containing water and ice. In the featured Juno photograph , an optical flash was captured in a large cloud vortex near Jupiter's north pole . During the next few months, Juno will perform several close sweeps over Jupiter's night side, likely allowing the robotic probe to capture more data and images of Jovian lightning . from NASA https://ift.tt/u8nLd5R

The multicolor, stereo imaging Mastcam-Z on the Perseverance rover zoomed in to capture this 3D close-up (get out your red/blue glasses) of the Mars Ingenuity helicopter on mission sol 45. That's Earth-date 2021 April 5. Casting a shadow on the Martian surface, Ingenuity is standing alone on its four landing legs next to the rover's wheel tracks. The experimental helicopter's solar panel, charging batteries that keep it warm through the cold Martian nights and power its flight, sits just above Ingenuity's two 1.2 meter (4 foot) long counter-rotating blades. Thirteen sols later , on April 19, Ingenuity became the first aircraft to perform powered, controlled flight on another planet. It has since gone on to complete more than 50 flights through the thin atmosphere of Mars. from NASA https://ift.tt/xkP65sa

Over 500,000 light years across, NGC 6872 (top right) is a truly enormous barred spiral galaxy , at least 5 times the size of our own very large Milky Way. The appearance of this giant galaxy's distorted and stretched out spiral arms suggests the magnificent wings of a giant bird. Of course its popular moniker is the Condor galaxy. It lies about 200 million light-years distant toward the southern constellation Pavo, the Peacock. Lined with star-forming regions , the distorted spiral arms are due to NGC 6872's gravitational interaction with the nearby smaller galaxy IC 4970 , seen just above the giant galaxy's core. The Pavo galaxy group's dominant giant elliptical galaxy, NGC 6876 is below and left of the soaring Condor galaxy. from NASA https://ift.tt/kviA2KX

Cosmic dust clouds cross a rich field of stars in this telescopic vista near the northern boundary of Corona Australis , the Southern Crown. Part of a sprawling molecular cloud complex this star forming region is a mere 500 light-years away. That's about one third the distance of the more famous stellar nursery known as the Orion Nebula. The 2 degree wide frame would span 15 light-years at the clouds' estimated distance. Mixed with bright nebulosities the dust clouds effectively block light from more distant background stars in the Milky Way and obscure from view embedded stars still in the process of formation. Large dark nebula Bernes 157 is on the left. To its right are a group of pretty reflection nebulae cataloged as NGC 6726, 6727, 6729, and IC 4812. Their characteristic blue color is produced as light from hot stars is reflected by the cosmic dust. The more compact NGC 6729 surrounds young variable star R Coronae Australis . Just below it, filamentary arcs and loop...

Does the Sun follow the same path every day? No . The Sun's path changes during the year, tracing a longer route during the summer than the winter. Pictured here , the Sun's arc was captured from noon to sunset on three days, from highest in the sky to lowest: summer solstice , equinox , and winter solstice . The images were taken near Gatto Corvino Village in Sicily , Italy in 2020 and 2021. The path and time the Sun spends in the sky is more important in determining the season than how close the Earth is to the Sun . In fact, the Earth is closest to the Sun in January, during northern winter. Today is a solstice , so today the Sun is taking its longest path of the year across the sky in Earth's northern hemisphere , but the shortest path in the southern hemisphere . from NASA https://ift.tt/bpB680k

Have you seen the bird in the Milky Way? Beyond the man in the Moon , the night sky is filled with stories, and cultures throughout history have projected some of their most enduring legends onto the stars and dust above. Generations of people see these celestial icons, hear their associated stories, and pass them down. Pictured here is not only a segment of the central band of our Milky Way galaxy , but, according to folklore of several native peoples of Uruguay , the outline of a great bird called Ñandú . Furthermore, Ñandú's footprint is associated with the Southern Cross asterism. In the foreground, in silhouette , is a statue of María Micaela Guyunusa , an indigenous woman of the Charrúa people who lived in the 1800s and endures as a symbol of colonial resistance. The composite image was taken in mid-April in Cabo Polonio , Uruguay, with the Atlantic Ocean in the background. from NASA https://ift.tt/FS3DKrA

The center of the Lagoon Nebula is a whirlwind of spectacular star formation. Visible near the image center, at least two long funnel-shaped clouds, each roughly half a light-year long, have been formed by extreme stellar winds and intense energetic starlight . A tremendously bright nearby star, Herschel 36 , lights the area. Vast walls of dust hide and redden other hot young stars. As energy from these stars pours into the cool dust and gas, large temperature differences in adjoining regions can be created generating shearing winds which may cause the funnels . This picture, spanning about 15 light years, combines images taken in four colors by the orbiting Hubble Space Telescope . The Lagoon Nebula , also known as M8 , lies about 5000 light years distant toward the constellation of the Archer ( Sagittarius ). from NASA https://ift.tt/a9fZUpM

Why would clouds form a hexagon on Saturn? Nobody is sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System . Acquiring its first sunlit views of far northern Saturn in late 2012 , the Cassini spacecraft's wide-angle camera recorded this stunning, false-color image of the ringed planet's north pole. The composite of near-infrared image data results in red hues for low clouds and green for high ones, giving the Saturnian cloudscape a vivid appearance. This and similar images show the stability of the hexagon even 20+ years after Voyager. Movies of Saturn's North Pole show the cloud structure maintaining its hexagonal structure while rotating. Unlike individual clouds appearing like a hexagon on Earth , the Saturn cloud pattern appears to have six well defined sides of nearly equal length. Four Earth s could fit inside the hexagon . Beyond the cloud tops at the upper right,...

Recorded during 2017, timelapse sequences from the International Space Station are compiled in this serene video of planet Earth at Night . Fans of low Earth orbit can start by enjoying the view as green and red aurora borealis slather up the sky . The night scene tracks from northwest to southeast across North America, toward the Gulf of Mexico and the Florida coast. A second sequence follows European city lights, crosses the Mediterranean Sea, and passes over a bright Nile river in northern Africa. Seen from the orbital outpost, erratic flashes of lightning appear in thunder storms below and stars rise above the planet's curved horizon through a faint atmospheric airglow . Of course, from home you can always check out the vital signs of Planet Earth Now. from NASA https://ift.tt/D4FRpZ9

This serene view from the coast of Sweden looks across the Baltic sea and compresses time, presenting the passage of one night in a single photograph. From sunset to sunrise, moonlight illuminates the creative sea and skyscape. Fleeting clouds, fixed stars, and flowing northern lights leave their traces in planet Earth's sky . To construct the timelapse image, 3296 video frames were recorded on the night of June's Full Moon between 7:04pm and 6:35am local time. As time progresses from left to right, a single column of pixels was taken from the corresponding individual frame and combined in sequence into a single digital image 3296 pixels wide. from NASA https://ift.tt/CUE3ueo

Messier 15 is an immense swarm of over 100,000 stars. A 13 billion year old relic of the early formative years of our galaxy it's one of about 170 globular star clusters that still roam the halo of the Milky Way. Centered in this sharp reprocessed Hubble image, M15 lies some 35,000 light-years away toward the constellation Pegasus. Its diameter is about 200 light-years, but more than half its stars are packed into the central 10 light-years or so, making one of the densest concentrations of stars known. Hubble-based measurements of the increasing velocities of M15's central stars are evidence that a massive black hole resides at the center of the dense cluster. M15 is also known to harbour a planetary nebula . Called Pease 1 (aka PN Ps 1), it can be seen in this image as a small blue blob below and just right of center. from NASA https://ift.tt/Sy4Yeqr

There is no sea on Earth large enough to contain the Shark nebula. This predator apparition poses us no danger as it is composed only of interstellar gas and dust . Dark dust like that featured here is somewhat like cigarette smoke and created in the cool atmospheres of giant stars . After being expelled with gas and gravitationally recondensing , massive stars may carve intricate structures into their birth cloud using their high energy light and fast stellar wind s as sculpting tools. The heat they generate evaporates the murky molecular cloud as well as causing ambient hydrogen gas to disperse and glow red. During disintegration, we humans can enjoy imagining these great clouds as common icons , like we do for water clouds on Earth. Including smaller dust nebulae such as Lynds Dark Nebula 1235 and Van den Bergh 149 & 150, the Shark nebula spans about 15 light years and lies about 650 light years away toward the constellation of the King of Aethiopia ( Cepheus ). fr...

Jupiter's moons circle Jupiter. The featured video depicts Europa and Io, two of Jupiter's largest moons , crossing in front of the grand planet's Great Red Spot , the largest known storm system in our Solar System . The video was composed from images taken by the robotic Cassini spacecraft as it passed Jupiter in 2000, on its way to Saturn. The two moons visible are volcanic Io , in the distance, and icy Europa . In the time-lapse video, Europa appears to overtake Io, which is odd because Io is closer to Jupiter and moves faster. The explanation is that the motion of the fast Cassini spacecraft changes the camera location significantly during imaging. Jupiter is currently being visited by NASA 's robotic Juno spacecraft , while ESA 's Jupiter Icy Moons Explorer (JUICE), launched in April, is enroute. from NASA https://ift.tt/stOfRul