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What does a black hole look like? To find out, radio telescopes from around the Earth coordinated observations of black holes with the largest known event horizon s on the sky. Alone, black holes are just black , but these monster attractors are known to be surrounded by glowing gas. This first image resolves the area around the black hole at the center of galaxy M87 on a scale below that expected for its event horizon . Pictured , the dark central region is not the event horizon, but rather the black hole's shadow -- the central region of emitting gas darkened by the central black hole's gravity. The size and shape of the shadow is determined by bright gas near the event horizon , by strong gravitational lensing deflections , and by the black hole's spin. In resolving this black hole's shadow , the Event Horizon Telescope (EHT) bolstered evidence that Einstein's gravity works even in extreme regions , and gave clear evidence that M87 has a central spinn...

A mere 600 light-years away, M44 is one of the closest star clusters to our solar system. Also known as the Praesepe or the Beehive cluster its stars are young though, about 600 million years old compared to our Sun's 4.5 billion years. Based on similar ages and motion through space, M44 and the even closer Hyades star cluster in Taurus are thought to have been born together in the same large molecular cloud. An open cluster spanning some 15 light-years, M44 holds 1,000 stars or so and covers about 3 full moons (1.5 degrees) on the sky in the constellation Cancer. Visible to the unaided eye, M44 has been recognized since antiquity. Described as a faint cloud or celestial mist long before being included as the 44th entry in Charles Messier's 18th century catalog, the cluster was not resolved into its individual stars until telescopes were available. A popular target for modern, binocular-equipped sky gazers, the cluster's few yellowish tinted , cool, red giants are sc...

By Sabrina Imbler from NYT Science https://ift.tt/81gxX0r

Sharp telescopic views of NGC 3628 show a puffy galactic disk divided by dark dust lanes. Of course, this portrait of the magnificent, edge-on spiral galaxy puts some astronomers in mind of its popular moniker, the Hamburger Galaxy. It also reveals a small galaxy nearby (below), likely a satellite of NGC 3628, and a very faint but extensive tidal tail . The drawn out tail stretches for about 300,000 light-years, even beyond the upper left edge of the frame. NGC 3628 shares its neighborhood in the local universe with two other large spirals M65 and M66 in a grouping otherwise known as the Leo Triplet . Gravitational interactions with its cosmic neighbors are likely responsible for creating the tidal tail, as well as the extended flare and warp of this spiral's disk. The tantalizing island universe itself is about 100,000 light-years across and 35 million light-years away in the northern springtime constellation Leo. from NASA https://ift.tt/DaRos0U

By James Gorman from NYT Science https://ift.tt/GoK2kRr

In the early hours of April 24 this bright Lyrid meteor flashed along the central Milky Way. For a moment, it cast a bright reflection across Lake Nian, Yunnan province, China. The annual Lyrid meteor shower , one of the oldest known, is active in late April, as our fair planet plows through dust left along the orbit of long-period comet Thatcher. The trail of the bright fireball points back toward the shower's radiant in the constellation Lyra high in the northern springtime sky and off the top of the frame. Just rising in that starry sky, light from a third quarter moon also cast a glow on the peaceful waters of the lake. from NASA https://ift.tt/i25BPoU

By Kenneth Chang from NYT Science https://ift.tt/QB2fnyk

By Alla Katsnelson from NYT Science https://ift.tt/HG0IfOZ

By Alanna Mitchell from NYT Science https://ift.tt/f64OurR

What is that large dark spot on Jupiter? It's the shadow of Io , one of Jupiter 's largest moons. When Jupiter's moons cross between the Jovian giant and the Sun, they created shadows just like when the Earth's moon crosses between the Earth and the Sun. Also like on Earth, if you were in a dark shadow on Jupiter , you would see a moon completely eclipse the Sun . Unlike on Earth, moon shadow s occur most days on Jupiter -- what's more unusual is that a spacecraft was close enough to record one with a high-resolution image . That spacecraft, Juno , was passing so close to Jupiter in late February that nearby clouds and the dark eclipse shadow appear relatively large . Juno has made many discoveries about our Solar System 's largest planet, including, recently, rapidly expanding circular auroras . from NASA https://ift.tt/hZMcCyN

The world is waking up to a picturesque planet parade. Just before dawn, the eastern skies over much of planet Earth are decorated by a notable line of familiar planets. In much of Earth's northern hemisphere, this line of planets appears most nearly horizontal , but in much of Earth's southern hemisphere , the line appears more nearly vertical. Pictured over the Sydney Opera House in southern Australia , the planet line was captured nearly vertical about five days ago. From top to bottom, the morning planets are Saturn , Mars , Venus , and Jupiter . As April ends, the angular distance between Venus and Jupiter will gradually pass below a degree as they switch places. Then, as May ends, Jupiter will pass near Mars as those two planets switch places . In June, the parade will briefly expand to include Mercury. from NASA https://ift.tt/KbjWaV8

In one of the brightest parts of Milky Way lies a nebula where some of the oddest things occur. NGC 3372, known as the Great Nebula in Carina , is home to massive stars and changing nebulas. The Keyhole Nebula (NGC 3324), the bright structure just below the image center, houses several of these massive stars. The entire Carina Nebula , captured here , spans over 300 light years and lies about 7,500 light-years away in the constellation of Carina . Eta Carinae , the most energetic star in the nebula, was one of the brightest stars in the sky in the 1830s, but then faded dramatically. While Eta Carinae itself maybe on the verge of a supernova explosion, X-ray images indicate that much of the Great Nebula in Carina has been a veritable supernova factory . from NASA https://ift.tt/uv7YWVw

Just now, before you hit the button, two future universes are possible. After pressing the button, though, you will live in only one. A real-web version of the famous Schrödinger's cat experiment clicking the red button in the featured astronaut image should transform that image into a picture of the same astronaut holding one of two cats -- one living, or one dead. The timing of your click, combined with the wiring of your brain and the millisecond timing of your device, will all conspire together to create a result dominated , potentially, by the randomness of quantum mechanics . Some believe that your personally-initiated quantum decision will split the universe in two, and that both the live-cat and dead-cat universes exist in separate parts of a larger multiverse . Others believe that the result of your click will collapse the two possible universes into one -- in a way that could not have been predicted beforehand. Yet others believe that the universe is classically ...

A gorgeous spiral galaxy, Messier 104 is famous for its nearly edge-on profile featuring a broad ring of obscuring dust lanes. Seen in silhouette against an extensive central bulge of stars, the swath of cosmic dust lends a broad brimmed hat-like appearance to the galaxy suggesting a more popular moniker, the Sombrero Galaxy. This sharp view of the well-known galaxy was made from over 10 hours of Hubble Space Telescope image data, processed to bring out faint details often lost in the overwhelming glare of M104's bright central bulge. Also known as NGC 4594, the Sombrero galaxy can be seen across the spectrum , and is host to a central supermassive black hole. About 50,000 light-years across and 28 million light-years away, M104 is one of the largest galaxies at the southern edge of the Virgo Galaxy Cluster. Still, the spiky foreground stars in this field of view lie well within our own Milky Way. from NASA https://ift.tt/wWknQGO

No sudden, sharp boundary marks the passage of day into night in this gorgeous view of ocean and clouds over our fair planet Earth . Instead, the shadow line or terminator is diffuse and shows the gradual transition to darkness we experience as twilight. With the Sun illuminating the scene from the right, the cloud tops reflect gently reddened sunlight filtered through the dusty troposphere, the lowest layer of the planet's nurturing atmosphere. A clear high altitude layer, visible along the dayside's upper edge, scatters blue sunlight and fades into the blackness of space. This picture was taken in June of 2001 from the International Space Station orbiting at an altitude of 211 nautical miles. Of course from home, you can check out the Earth Now. from NASA https://ift.tt/AI92UOd

By Adam Mann from NYT Science https://ift.tt/H1oEpbm

Fifty years ago , April 20, 1972, Apollo 16's lunar module Orion touched down on the Moon's near side in the south-central Descartes Highlands. While astronaut Ken Mattingly orbited overhead in Casper the friendly command and service module the Orion brought John Young and Charles Duke to the lunar surface. The pair would spend nearly three days on the Moon . Constructed from images (AS16-117-18814 to AS16-117-18820) taken near the end of their third and final surface excursion this panoramic view puts the lunar module in the distance toward the left. Their electric lunar roving vehicle in the foreground, Duke is operating the camera while Young aims the high gain communications antenna skyward, toward planet Earth . from NASA https://ift.tt/7aFhjKi

There's an interesting sky to see if you wake up before the Sun. Lined up on toward the eastern horizon are four planets in a row. The planets are so bright they can even be seen from the bright sky inside a city. In fact, the featured image was taken from New York City, USA, with the foreground highlighted by the RFK ( Triborough ) Bridge . Pictured, the planets are, left to right, Jupiter , Venus , Mars , and Saturn . The planets all appear in a row because they all orbit the Sun in the same plane . This plane, called the ecliptic plane , was created in the early days of our Solar System and includes all planets, including Earth . The morning planet parade will continue throughout April and May, and will even be joined by Mercury in June. from NASA https://ift.tt/8IHNcML

The eggs from this gigantic chicken may form into stars. The featured emission nebula, shown in scientifically assigned colors, is cataloged as IC 2944 but known as the Running Chicken Nebula for the shape of its greater appearance. Seen toward the bottom of the image are small, dark molecular clouds rich in obscuring cosmic dust . Called Thackeray's Globules for their discoverer , these "eggs" are potential sites for the gravitational condensation of new stars , although their fates are uncertain as they are also being rapidly eroded away by the intense radiation from nearby young stars. Together with patchy glowing gas and complex regions of reflecting dust, these massive and energetic stars form the open cluster Collinder 249. This gorgeous skyscape spans about 60 light-years at the nebula's estimated 6,500 light-year distance. from NASA https://ift.tt/hVlD5RO

The mission was to document night-flying birds -- but it ended up also documenting a beautiful sky. The featured wide-angle mosaic was taken over the steppe golden fields in Mértola , Portugal in 2020. From such a dark location, an immediately-evident breathtaking glow arched over the night sky: the central band of our Milky Way galaxy . But this sky had much more. Thin clouds crossed the sky like golden ribbons. The planet Mars appeared on the far left, while the planets Saturn and Jupiter were also simultaneously visible -- but on the opposite side of the sky, here seen on the far right. Near the top of the image the bright star Vega can be found, while the far-distant and faint Andromeda Galaxy can be seen toward the left, just below Milky Way's arch . As the current month progresses, several planets are lining up in the pre-dawn sky: Jupiter , Venus, Mars , and Saturn . from NASA https://ift.tt/9xktvBM

By Benjamin Mueller from NYT Science https://ift.tt/Zj7lcnk

What's that approaching? Astronauts on board the International Space Station in 2010 first saw it far in the distance. Soon it enlarged to become a dark silhouette . As it came even closer, the silhouette appeared to be a spaceship. Finally, the object revealed itself to be the Space Shuttle Endeavour , and it soon docked as expected with the Earth-orbiting space station. Pictured here , Endeavour was imaged near Earth's horizon as it approached, where several layers of the Earth's atmosphere were visible. Directly behind the shuttle is the mesosphere , which appears blue. The atmospheric layer that appears white is the stratosphere , while the orange layer is Earth's Troposphere . Together, these thin layers of air -- collectively spanning less than 2 percent of Earth 's radius -- sustain us all in many ways, including providing oxygen to breath and a barrier to dangerous radiations from space . from NASA https://ift.tt/2K8zkol

Taken with a camera fixed to a tripod, many short exposures were aligned with the stars to unveil this beautiful, dark night sky. Captured near the rural village of Albany`a at the northeastern corner of Spain, the three stars of Orion's belt stretch across top center in the starry frame. Alnitak, the easternmost (left) of the belt stars is seen next to the more diffuse glow of the Flame Nebula and the dark notch of the famous Horsehead . Easily visible to the naked-eye The Great Nebula of Orion is below the belt stars. A mere 1,500 light-years distant, it is the closest large stellar nursery to our fair planet. Best seen in photographs, the broad and faint arc of Barnard's Loop seems to embrace Orion's brighter stars and nebulae though. In the northern spring the familiar northern winter constellation is setting. Near the western horizon toward lower right Orion's apparently bright blue supergiant Rigel just touches the branches of a pine tree. from NASA htt...

By Joey Roulette from NYT Science https://ift.tt/oJ0n6fx

By Robin George Andrews from NYT Science https://ift.tt/9hg8rAG

Wind-sharpened rocks known as ventifacts, cover this broad sloping plain in the foot hills of Mount Sharp, Gale crater, Mars. Dubbed gator-back rocks their rugged, scaly appearance is captured in these digitally stitched Mastcam frames from the Curiosity rover on mission sol 3,415 (March 15, 2022). Driving over gator-back rocks before has resulted in damage to the rover's wheels, so Curiosity team members decided to turn around and take another path to continue the rover's climb. Curiosity has been on an ascent of Gale crater's central 5.5 kilometer high mountain since 2014. As it climbs, it's been able to study layers shaped by water on Mars billions of years ago . from NASA https://ift.tt/IGon5ra

Spiral arms seem to swirl around the core of Messier 96 in this colorful, detailed portrait of a beautiful island universe . Of course M96 is a spiral galaxy , and counting the faint arms extending beyond the brighter central region it spans 100 thousand light-years or so. That's about the size of our own Milky Way. M96 is known to be 38 million light-years distant, a dominant member of the Leo I galaxy group . Background galaxies and smaller Leo I group members can be found by examining the picture. The most intriguing one is itself a spiral galaxy seen nearly edge on behind the outer spiral arm near the 1 o'clock position from center. Its bright central bulge cut by its own dark dust clouds, the edge-on background spiral appears to be about 1/5 the size of M96. If that background galaxy is similar in actual size to M96, then it would be about 5 times farther away . from NASA https://ift.tt/oTOeI2H

What created Devils Tower? The origin of this extraordinary rock monolith in Wyoming , USA is still debated, with a leading hypothesis holding that it is a hardened lava plume that never reached the surface to become a volcano. In this theory , the lighter rock that once surrounded the dense volcanic neck has now eroded away, leaving the dramatic tower . Known by Native Americans by names including Bear's Lodge and Great Gray Horn , the dense rock includes the longest hexagon al columns known, some over 180-meters tall. High above, the central band of the Milky Way galaxy arches across the sky. Many notable sky objects are visible, including dark strands of the Pipe Nebula and the reddish Lagoon Nebula to the tower's right. Green grass and trees line the foreground , while clouds appear near the horizon to the tower's left. Unlike many other international landmarks, mountaineers are permitted to climb Devils Tower . from NASA https://ift.tt/HOlTXML

Massive stars, abrasive winds, mountains of dust , and energetic light sculpt one of the largest and most picturesque regions of star formation in the Local Group of Galaxies . Known as N11 , the region is visible on the upper right of many images of its home galaxy, the Milky Way neighbor known as the Large Magellanic Cloud (LMC). The featured image was taken for scientific purposes by the Hubble Space Telescope and reprocessed for artistry . Although the section imaged above is known as NGC 1763 , the entire N11 emission nebula is second in LMC size only to the Tarantula Nebula . Compact globules of dark dust housing emerging young stars are also visible around the image. A recent study of variable stars in the LMC with Hubble has helped to recalibrate the distance scale of the observable universe , but resulted in a slightly different scale than found using the pervasive cosmic microwave background . from NASA https://ift.tt/riEGUJL

Typically, the International Space Station is visible only at night. Slowly drifting across the night sky as it orbits the Earth, the International Space Station (ISS) can be seen as a bright spot several times a year from many locations. The ISS is then visible only just after sunset or just before sunrise because it shines by reflected sunlight -- once the ISS enters the Earth's shadow, it will drop out of sight. The only occasion when the ISS is visible during the day is when it passes right in front of the Sun . Then, it passes so quickly that only cameras taking short exposures can visually freeze the ISS's silhouette onto the background Sun . The featured picture did exactly that -- it is actually a series of images taken earlier this month from Beijing , China with perfect timing. This image series was later combined with separate images taken at nearly the same time but highlighting the texture and activity on the busy Sun . The solar activity included numerous...

Was this image of the Moon's surface taken with a microscope? No -- it's a multi-temporal illumination map made with a wide-angle camera. To create it, the Lunar Reconnaissance Orbiter spacecraft collected 1,700 images over a period of 6 lunar days (6 Earth months), repeatedly covering an area centered on the Moon's south pole from different angles. The resulting images were stacked to produce the featured map -- representing the percentage of time each spot on the surface was illuminated by the Sun . Remaining convincingly in shadow , the floor of the 19-kilometer diameter Shackleton crater is seen near the map's center. The lunar south pole itself is at about 9 o'clock on the crater's rim. Crater floors near the lunar south and north poles can remain in permanent shadow , while mountain tops can remain in nearly continuous sunlight . Useful for future outposts , the shadowed crater floors could offer reservoirs of water-ice , while the sunlit mountain...

Fainter stars in the zodiacal constellation Capricornus are scattered near the plane of the ecliptic in this field of view. The two brightest ones at center aren't stars at all though, but the planets Mars and Saturn. Taken on the morning of April 4, the telescopic snapshot captured their tantalizing close conjunction in a predawn sky, the pair of planets separated by only about 1/3 of a degree. That's easily less than the apparent width of a Full Moon. Can you tell which planet is which? If you guessed Mars is the redder one , you'd be right. Above Mars, slightly fainter Saturn still shines with a paler yellowish tinge in reflected sunlight . Even at the low magnification, Saturn's largest and brightest moon Titan can be spotted hugging the planet very closely on the left. from NASA https://ift.tt/9lkbriN

By Kenneth Chang from NYT Science https://ift.tt/ebqMAzv

Only twenty-five years ago, Comet Hale-Bopp rounded the Sun and offered a dazzling spectacle in planet Earth's night skies. Digitized from the original astrophoto on 35mm color slide film, this classic image of the Great Comet of 1997 was recorded a few days after its perihelion passage on April 1, 1997 . Made with a camera and telephoto lens piggy-backed on a small telescope, the 10 minute long, hand-guided exposure features the memorable tails of Hale-Bopp , a whitish dust tail and blue ion tail. Here, the ion tail extends well over ten degrees across the northern sky. In all, Hale-Bopp was reported as visible to the naked eye from late May 1996 through September 1997. Also known as C/1995 O1, Hale-Bopp is recognized as one of the most compositionally pristine comets to pass through the inner Solar System. A visitor from the distant Oort cloud , the comet's next perihelion passage should be around the year 4380 AD. Do you remember Hale-Bopp ? from NASA https://ift.tt...

By Dennis Overbye from NYT Science https://ift.tt/w8syLVF

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. When you gaze at the star cloud with binoculars or small telescope 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 just above center , along with other clouds of dust and glowing nebulae toward the center of the Milky Way. from NASA https://ift.tt/CM3KBUf

Is Earendel the farthest star yet discovered? This scientific possibility started when the Hubble Space Telescope observed a huge cluster of galaxies . The gravitational lens effect of this cluster was seen to magnify and distort a galaxy far in the background. This distorted background galaxy -- so far away it has a redshift of 6.2 -- appears in the featured image as a long red string, while beads on that string are likely to be star clusters.   The galaxy cluster lens creates a line of maximum magnification line where superposed background objects may appear magnified many thousands of times. On the intersection between the galaxy line and the maximum magnification line is one "bead" which shows evidence of originating from a single bright star in the early universe -- now named Earendel. Future investigation s may include more imaging by Hubble to see how Earendel's brightness varies, and, quite possibly, by the new James Webb Space Telescope when i...

By Elizabeth Preston and Matt Cosby from NYT Science https://ift.tt/R3nZhrO

On the upper right, dressed in blue, is the Pleiades . Also known as the Seven Sisters and M45 , the Pleiades is one of the brightest and most easily visible open clusters on the sky. The Pleiades contains over 3,000 stars, is about 400 light years away, and only 13 light years across. Surrounding the stars is a spectacular blue reflection nebula made of fine dust . A common legend is that one of the brighter stars faded since the cluster was named. On the lower left, shining in red, is the California Nebula . Named for its shape, the California Nebula is much dimmer and hence harder to see than the Pleiades . Also known as NGC 1499 , this mass of red glowing hydrogen gas is about 1,500 light years away. Although about 25 full moons could fit between them , the featured wide angle, deep field image composite has captured them both . A careful inspection of the deep image will also reveal the star forming region IC 348 and the molecular cloud LBN 777 (the Baby Eagle Neb...

No, the car was not in danger of being vacuumed into space by the big sky vortex. For one reason, the vortex was really an aurora , and since auroras are created by particles striking the Earth from space, they do not create a vacuum . This rapidly developing auroral display was caused by a Coronal Mass Ejection from the Sun that passed by the Earth closely enough to cause a ripple in Earth's magnetosphere . The upper red parts of the aurora occur over 250 kilometers high with its red glow created by atmospheric atomic oxygen directly energized by incoming particles. The lower green parts of the aurora occur over 100 kilometers high with its green glow created by atmospheric atomic oxygen energized indirectly by collisions with first-energized molecular nitrogen. Below 100 kilometers, there is little atomic oxygen, which is why auroras end abruptly. The concentric cylinder s depict a dramatic auroral corona as seen from the side. The featured image was created from a s...

Our Earth is not at rest. The Earth moves around the Sun . The Sun orbits the center of the Milky Way Galaxy . The Milky Way Galaxy orbits in the Local Group of Galaxies . The Local Group falls toward the Virgo Cluster of Galaxies . But these speeds are less than the speed that all of these objects together move relative to the cosmic microwave background radiation (CMBR). In the featured all-sky map from the COBE satellite in 1993, microwave light in the Earth's direction of motion appears blueshifted and hence hotter, while microwave light on the opposite side of the sky is redshifted and colder. The map indicates that the Local Group moves at about 600 kilometers per second relative to this primordial radiation . This high speed was initially unexpected and its magnitude is still unexplained. Why are we moving so fast ? What is out there? from NASA https://ift.tt/kCVHx2P

This almost otherworldly display of northern lights was captured in clear skies during the early hours of March 31 from 44 degrees north latitude, planet Earth. In a five second exposure the scene looks north from Martinique Beach Provincial Park in Nova Scotia, Canada. Stars of the W-shaped constellation Cassiopeia shine well above the horizon, through the red tint of the higher altitude auroral glow. Auroral activity was anticipated by skywatchers alerted to the possibility of stormy space weather by Sun-staring spacecraft. The predicted geomagnetic storm was sparked as a coronal mass ejection, launched from prolific solar active region 2975 , impacted our fair planet's magnetosphere . from NASA https://ift.tt/4V0rNlv

By Kenneth Chang from NYT Science https://ift.tt/cseV0lt

The natural filter of a hazy atmosphere offered this recognizable architecture and sunset view on March 27. Dark against the solar disk, large sunspots in solar active regions 2975 and 2976 are wedged between the Duomo of Pisa and its famous Leaning Tower . Only one day later, Sun-staring spacecraft watched active region 2975 unleash a frenzy of solar flares along with two coronal mass ejections. The largest impacted the magnetosphere on March 31 triggering a geomagnetic storm and aurorae in high-latitude night skies. On March 30 , active region 2975 erupted again with a powerful X-class solar flare that caused a temporary radio blackout on planet Earth. from NASA https://ift.tt/BVAjD4T

Some 60 million light-years away in the southerly constellation Corvus , two large galaxies are colliding. Stars in the two galaxies, cataloged as NGC 4038 and NGC 4039 , very rarely collide in the course of the ponderous cataclysm that lasts for hundreds of millions of years. But the galaxies' large clouds of molecular gas and dust often do, triggering furious episodes of star formation near the center of the cosmic wreckage . Spanning over 500 thousand light-years, this stunning view also reveals new star clusters and matter flung far from the scene of the accident by gravitational tidal forces. The remarkably sharp ground-based image , an accumulation of 88 hours of exposure captured during 2012-2021, follows the faint tidal tails and distant background galaxies in the field of view. The suggestive overall visual appearance of the extended arcing structures gives the galaxy pair, also known as Arp 244, its popular name - The Antennae. from NASA https://ift.tt/QUdrJ1a

What do you call a cosmic puzzle that no one expected to see? In this case, Odd Radio Circle s, aka ORCs. ORC-1 typifies the enigmatic five objects, only visible at radio frequencies , that were serendipitously discovered in 2019 using the new Australia n SKA Pathfinder radio array. The final image in the featured video uses 2021 data from the South Africa n MeerKAT array to reveal more detail. The radio data, assigned turquoise colors, are combined with a Dark Energy Survey optical/ IR map. The animated artist’s illustration explores just one idea about the ORC s’ origins. If two supermassive black holes merge in the center of a galaxy, the associated shockwave s could generate rings of radio radiation. These grow to fill the video frame. The video zooms out so the expansion the ORC can be tracked until it is about a million light-year s across. Fortunately, the up-coming Square Kilometer Array can help test this and other promising scenarios. from NASA https://ift.tt...

By Matt Kaplan from NYT Science https://ift.tt/06Byek2

When two planets pass on the night sky, they can usually be seen near each other for a week or more. In the case of this planetary conjunction , Venus and Mars passed within 4 degrees of each other earlier this month . The featured image was taken a few days prior, when Venus was slowing rising in the pre-dawn sky, night by night, while Mars was slowly setting. The image, a four-part mosaic, was captured in Brazil from the small town Teresópolis . Besides Venus and Mars , the morning sky now also includes the more distant planet Saturn . Of course, these conjunctions are only angular -- Venus, Mars, and Saturn continue to orbit the Sun in very different parts of our Solar System . Next week, the angle between Saturn and Mars will drop to below a quarter of a degree . from NASA https://ift.tt/1sC0AOr

The southernmost part of the Milky Way contains not only the stars of the Southern Cross, but the closest star system to our Sun -- Alpha Centauri. The Southern Cross itself is topped by the bright, yellowish star Gamma Crucis . A line from Gamma Crucis through the blue star at the bottom of the cross, Acrux , points toward the south celestial pole , located just above the small island in the featured picture -- taken in early March. That island is Madivaru of the Maldives in the Indian Ocean . Against faint Milky Way starlight, the dark Coal Sack Nebula lies just left of the cross, while farther left along the Milky Way are the bright stars Alpha Centauri (left) and Beta Centauri (Hadar). Alpha Centauri A, a Sun-like star anchoring a three-star system with exoplanets , is a mere 4.3 light-years distant. Seen from Alpha Centauri, our own Sun would be a bright yellowish star in the otherwise recognizable constellation Cassiopeia . from NASA https://ift.tt/n0BFCMX

Why would the surface of Titan light up with a blinding flash? The reason: a sunglint from liquid seas. Saturn's moon Titan has numerous smooth lakes of methane that, when the angle is right, reflect sunlight as if they were mirrors. Pictured here in false-color, the robotic Cassini spacecraft that orbited Saturn from 2004 to 2017 imaged the cloud-covered Titan in 2014 in different bands of cloud-piercing infrared light . This specular reflection was so bright it saturated one of Cassini's infrared cameras. Although the sunglint was annoying -- it was also useful . The reflecting regions confirm that northern Titan houses a wide and complex array of seas with a geometry that indicates periods of significant evaporation. During its numerous passes of our Solar System 's most mysterious moon, Cassini has revealed Titan to be a world with active weather -- including times when it rains a liquefied version of natural gas . from NASA https://ift.tt/SaREW8b