A View from Earth s Shadow

This serene sand and skyscape finds the

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A Digital Lunar Eclipse

APOD: 2022 May 19 - A Digital Lunar Eclipse Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 19 A Digital Lunar Eclipse Image Credit &Copyright:Michael Cain Explanation: Recorded on May 15/16 this sequence of exposuresfollows the Full Moon during a total lunar eclipse as it arcsabove treetops in the clearing skies of central Florida.A frame taken every 5 minutes by a digital camerashows the progression of the eclipse over three hours.The bright lunar disk grows dark and red as itglides through planet Earth's shadow.In fact, counting the central frames in the sequencemeasures the roughly 90 minuteduration of the total phase of this eclipse.Around 270 BC, the Greek astronomerAristarchusalso measured the duration of total lunar eclipses,but probablywithout the benefitof digital watches and cameras.Still,using geometry hedevised a simple and impressively accurate way to calculatethe Moon's distance in terms of the radius of planet Earth,from the eclipse duration. Tomorrow's picture: a view from Earth's shadow<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important NoticesA service...

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A Jewel on the Flower Moon

APOD: 2022 May 18 - A Jewel on the Flower Moon Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 18 A Jewel on the Flower Moon Image Credit &Copyright:Tomas Slovinsky Explanation: Cloudy skies plagued some sky watchers on Sunday as May'sFull Flower Moonslipped through Earth's shadow in atotal lunar eclipse.In skies above Chile's Atacama desert this telephoto snapshot stillcaptured an awesome spectacle though.Seen through thin high cirrus clouds just before totality began,a last sliver of sunlit crescent glistens like a hazyjewel atop the mostly shadowed lunar disk.This full moon was near perigee,the closest point inits elliptical orbit.It passed near the center of Earth'sdark umbral shadow duringthe 90 minute long total eclipse phase.Faintly suffused with sunlight scattered by the atmosphere, the umbralshadow itself gave the eclipsed moon a reddened appearance and thevery dramatic popular moniker of aBlood Moon. Tomorrow's picture: pixels in space<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important NoticesA service of:ASD atNASA /GSFC& Michigan Tech. U.

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NGC 1316: After Galaxies Collide

APOD: 2022 May 17 - NGC 1316: After Galaxies Collide Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 17 NGC 1316: After Galaxies Collide Image Credit & Copyright: Capture: Greg Turgeon; Processing: Kiko Fairbairn Explanation: Astronomers turn detectives when trying to figure out the cause of startling sights like NGC 1316. Investigations indicate that NGC 1316is an enormous elliptical galaxy that started, about 100 million years ago, to devour a smaller spiral galaxy neighbor, NGC 1317, just on the upper right.Supporting evidence includes the dark dust lanes characteristic of aspiral galaxy,and faint swirls and shells of stars and gas visible in this wide and deep image.One thing that >remains unexplained is the unusually small globular star clusters, seen as faint dots on the image.Most elliptical galaxies have more and brighter globular clusters thanNGC 1316. Yet the observed globulars are too old to have been created by the recent spiral collision. One hypothesis is that these globulars survive from an even earlier galaxy that was subsumed into NGC 1316.Another surprising attribute of NGC 1316, also known as Fornax A, is its giant lobes of...

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Milky Way over French Alp Hoodoos

Real castles aren't this old.

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Colors of the Moon

APOD: 2022 May 15 - Colors of the Moon Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 15 Colors of the Moon Image Credit &Copyright: Marcella Giulia Pace Explanation: What color is the Moon?It depends on the night. Outside of the Earth's atmosphere, the dark Moon, which shines by reflected sunlight, appears a magnificently brown-tinged gray. Viewed from inside the Earth's atmosphere, though, the moon can appear quite different. The featured image highlights a collection of apparent colors of the full moon documented by one astrophotographer over 10 years from different locations across Italy.A red or yellow colored moon usually indicates a moon seen near the horizon. There, some of the blue light has been scattered away by a long path through the Earth's atmosphere, sometimes laden with fine dust.A blue-colored moon is more rare and can indicate a moon seen through an atmosphere carrying larger dust particles. What created the purple moon is unclear -- it may be a combination of several effects. The last image captures the total lunar eclipse of 2018 July -- where the moon, in Earth's shadow, appeared...

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Ice Halos by Moonlight

APOD: 2022 May 14 - Ice Halos by Moonlight Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 14 Ice Halos by Moonlight Image Credit &Copyright: Alan Dyer, Amazingsky.com,TWAN Explanation: An almost full moon on April 15 brought theseluminous apparitions to a northern spring nightover Alberta Canada.On that night, bright moonlightrefracted and reflected by hexagonal ice crystals inhigh clouds created acomplex of halosand arcs more commonlyseen by sunlight in daytime skies.While the colors of the arcs and moondogs or paraselenae werejust visible to the unaided eye, a blend of exposures rangingfrom 30 seconds to 1/20 second was used to render thismoonlit wide-angle skyscape.The Big Dipper at the top of the frame sits just abovea smiling and rainbow-huedcircumzenithal arc.With Arcturus left and Regulus toward the rightthe Moon is centered in its often spotted22 degree halo.May 15 will also see the bright light of a Full Moon shiningin Earth's night skies.Tomorrow's Full Moon will be dimmed for a while though,as it slides throughEarth's shadow in a totallunar eclipse. Watch:May 15-16 Total Lunar Eclipse Tomorrow's picture: colors of the moon<| Archive| Submissions | Index| Search| Calendar| RSS|...

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The Milky Way's Black Hole

APOD: 2022 May 13 - The Milky Way's Black Hole Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 13 The Milky Way's Black Hole Image Credit: X-ray - NASA/CXC/SAO,IR - NASA/HST/STScI;Inset:Radio - Event Horizon Telescope Collaboration Explanation: There's a black holeat the center of the Milky Way.Stars are observed to orbita very massive andcompact objectthere known as Sgr A* (say "sadge-ay-star").But this just released radio image (inset) from planet Earth'sEvent Horizon Telescope is thefirst direct evidence of the Milky Way's central black hole.As predicted by Einstein's Theory of General Relativity,the four million solar mass black hole's strong gravityis bending light and creating a shadow-like dark central regionsurrounded by a bright ring-like structure.Supporting observations made byspace-based telescopes and ground-based observatoriesprovide a wider view of the galactic center's dynamic environmentand an importantcontext for the Event Horizon Telescope's black hole image.The main panel imageshows the X-ray data from Chandra and infrared data from Hubble.While the main panel is about 7 light-years across,the Event Horizon Telescope inset image itself spans a mere 10light-minutesat the center of our galaxy,some 27,000 light-years away. Tomorrow's picture: ice halos by moonlight<|...

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Young Stars of NGC 346

APOD: 2022 May 12 - Young Stars of NGC 346 Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 12 Young Stars of NGC 346 Image Credit: NASA,ESA- acknowledgement:Antonella Nota (ESA/STScI)et al., Explanation: The massive stars of NGC 346are short lived, but veryenergetic.The star cluster is embedded inthe largest star forming region in theSmall Magellanic Cloud,some 210,000 light-years distant.Their winds and radiation sweep out an interstellarcavern in the gas and dust cloud about 200 light-years across,triggering star formation and sculptingthe region's dense inner edge.Cataloged as N66, the star forming region also appears tocontain a large population of infant stars.A mere 3 to 5 million years old and not yetburning hydrogenin their cores, theinfant starsare strewn about the embedded star cluster.In this false-colorHubble Space Telescope image,visible and near-infrared light are seen as blue and green,while light from atomic hydrogen emission is red. Tomorrow's picture: pixels in space<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important NoticesA service of:ASD atNASA /GSFC& Michigan Tech. U.

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Gravity s Grin

APOD: 2022 May 11 - Gravity s Grin Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 11 Gravity's Grin Image Credit: X-ray - NASA / CXC /J. Irwin et al. ;Optical - NASA/STScI Explanation: AlbertEinstein'sgeneral theory of relativity, published over 100 yearsago, predicted the phenomenon of gravitational lensing.And that's what gives these distant galaxies such a whimsicalappearance,seenthrough the looking glass of X-ray and opticalimage data from the Chandra and Hubble space telescopes.Nicknamed the Cheshire Cat galaxy group, the group's twolarge elliptical galaxies are suggestively framed by arcs.The arcs are optical imagesof distant background galaxieslensed by the foreground group's total distributionof gravitational mass.Of course, that gravitational mass is dominatedby dark matter.The two large elliptical "eye" galaxies representthe brightest members of their own galaxy groups which are merging.Their relative collisional speed of nearly 1,350 kilometers/secondheats gas to millions of degrees producing the X-ray glow shownin purple hues.Curiouser aboutgalaxy group mergers?The Cheshire Catgroupgrinsin the constellation Ursa Major, some 4.6 billion light-years away. Tomorrow's picture: pixels in space<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell...

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NGC 6334: The Cats Paw Nebula

APOD: 2022 May 10 - NGC 6334: The Cats Paw Nebula Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 10 NGC 6334: The Cat's Paw Nebula Image Credit & Copyright: Stefan Steve Bemmerl & Team Wolfatorium (Hakos/Namibia) Explanation: Nebulas are perhaps as famous for being identified with familiar shapes as perhaps cats are for getting into trouble. Still, no known cat could have created the vast Cat's Paw Nebulavisible toward the constellation of the Scorpion (Scorpius. At 5,500 light years distant, Cat's Paw is an emission nebula with a red color that originates from an abundance of ionized hydrogen atoms. Alternatively known as the Bear Claw Nebula and cataloged as NGC 6334, stars nearly ten times the mass of our Sun have been born there in only the past few million years.Pictured here is a deep field image of the Cat's Paw Nebula in light emitted by hydrogen, oxygen, and sulfur. Explore Your Universe: Random APOD Generator Tomorrow's picture: more cats in space <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell...

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A Martian Eclipse: Phobos Crosses the Sun

APOD: 2022 May 9 - A Martian Eclipse: Phobos Crosses the Sun Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. A Martian Eclipse: Phobos Crosses the Sun Video Credit: NASA,JPL-Caltech,ASUMSSS,SSI Explanation: What's that passing in front of the Sun?It looks like a moon, but it can't be Earth's Moon, because it isn't round.It's the Martian moon Phobos. The featured video was taken from the surface of Mars a month ago by the Perseverance rover.Phobos, at 11.5 kilometers across, is 150 times smaller than Luna (our moon) in diameter, but also 50 times closer to its parent planet. In fact, Phobos is so close to Mars that it is expected to break up and crash into Mars within the next 50 million years. In the near term, the low orbit of Phobos results in more rapid solar eclipses than seen from Earth.The featured video is shown in real time -- the transit really took about 40 seconds,as shown.The videographer -- the robotic rover Perseverance (Percy) -- continues to explore Jezero Crater on Mars,searching not only for clues to the watery history of the now dry world,but...

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Spiral Galaxy NGC 1512: The Inner Rings

APOD: 2022 May 8 - Spiral Galaxy NGC 1512: The Inner Rings Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 8 Spiral Galaxy NGC 1512: The Inner Rings Image Credit: NASA, ESA, Hubble Space Telescope Explanation: Most galaxies don't have any rings -- why does this galaxy have two? To begin, the bright band near NGC 1512's center is a nuclear ring, a ring that surrounds the galaxy center and glows brightly with recently formed stars.Most stars and accompanying gas and dust, however, orbit the galactic center in a ring much further out -- here seen near the image edge.This ring is called, counter-intuitively, the inner ring. If you look closely, you will see this the inner ring connects ends of a diffuse central bar that runs horizontally across the galaxy.These ring structures are thought to be caused by NGC 1512's own asymmetries in a drawn-out process called secular evolution. The gravity of these galaxy asymmetries, including the bar of stars, cause gas and dust to fall from the inner ring to the nuclear ring, enhancing this ring's rate of star formation. Some...

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Firefall by Moonlight

APOD: 2022 May 7 - Firefall by Moonlight Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 7 Firefall by Moonlight Image Credit &Copyright:Tara Mostofi Explanation: On certain dates in February, anelusive firefall can be spotted at sunset inYosemite National Park,when water flows, the weather cooperatesand the direction to the setting Sun is just right.Often photographed from vantage points below, at the right moment the park'sseasonal Horsetail Fallis isolated in the shadows of thesteep walls of El Capitan.Then, still illuminated with rays of reddened sunlightthe waterfall briefly takes on a dramatic, fiery appearance.But aHorsetail firefallcan be photographed by moonlight too.Even more elusive by moonlight, the firefall effect can also be seenwhen a bright Moon sets at the right direction along the western horizon.And skies were clear enough for this well-planned imaging of an ephemeral Horsetail firefall,lit by a bright gibbous Moon setting in the early morning hours of April 15. Tomorrow's picture: the inner rings<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important...

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NGC 3572 and the Southern Tadpoles

APOD: 2022 May 6 - NGC 3572 and the Southern Tadpoles Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 6 NGC 3572 and the Southern Tadpoles Image Credit &Copyright:Carlos Taylor Explanation: This cosmic skyscapefeatures glowing gas and dark dust cloudsalong side the young stars of NGC 3572.A beautiful emission nebula and star cluster it sailsfar southern skieswithin the nautical constellation Carina.Stars from NGC 3572 are toward top center in the telescopicframe that would measure about 100 light-years across at the cluster'sestimated distance of 9,000 light-years.The visible interstellar gas and dust is part of the star cluster'snatal molecular cloud.Dense streamers of materialwithin the nebula, eroded by stellar winds and radiation,clearly trail away from the energetic young stars.They are likely sites of ongoing star formation with shapesreminiscent of theTadpoles of IC 410better known to northern skygazers. In the coming tens to hundreds of millions of years, gas and stars inthe cluster will be dispersed though, by gravitational tides and byviolentsupernova explosionsthat end the short lives of the massive cluster stars. Tomorrow's picture: firefall by moonlight<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD|...

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NGC 3521: Galaxy in a Bubble

APOD: 2022 May 5 - NGC 3521: Galaxy in a Bubble Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 5 NGC 3521: Galaxy in a Bubble Image Credit &Copyright:Mark HansonandMike Selby Explanation: Gorgeous spiral galaxy NGC 3521is a mere 35 million light-years away,toward the northernspringtime constellation Leo.Relatively bright in planet Earth's sky, NGC 3521 iseasily visible in small telescopes but often overlooked byamateur imagers in favor of other Leo spiral galaxies,like M66 and M65.It's hard to overlook inthis colorfulcosmic portrait though.Spanning some 50,000 light-years the galaxy sportscharacteristicpatchy, irregular spiral arms laced with dust, pink star forming regions,andclusters of young, blue stars.This deep image also finds NGC 3521 embedded in fainter,gigantic, bubble-like shells.The shells are likely tidal debris, streams of stars tornfrom satellite galaxies that haveundergone mergerswith NGC 3521 in the distant past. Tomorrow's picture: southern tadpoles<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific rights apply.NASA WebPrivacy Policy and Important NoticesA service of:ASD atNASA /GSFC& Michigan Tech. U.

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Planets Over Egyptian Pyramid

APOD: 2022 May 4 - Planets Over Egyptian Pyramid Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 4 Planets Over Egyptian Pyramid Image Credit & Copyright: Osama Fatehi Explanation: The early morning planet parade continues.Visible the world over, the planets Jupiter, Venus, Mars and Saturn have been lining up in the pre-dawn sky since mid-April.In the featured image taken last month, these planets were captured over the Step Pyramid of Djoser, a UNESCO World Heritage Site.Located in the Saqqara necropolis of Egypt, the pyramid was constructed in the 27th century BC and is one of the oldest pyramids known. The two-image composite includes a foreground image taken during evening blue hour, and a background image captured from the same location the following morning. The morning planet line-up is slowly changing. At the end of last month, planets Jupiter and Venus switched places, while at the end of this month, Jupiter and Mars will switch after passing within one-degree of each other.Of course, this picturesque planetary angular alignment is a coincidence, as all of these worlds continue to orbit the Sun as they have...

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Mercurys Sodium Tail

APOD: 2022 May 3 - Mercurys Sodium Tail Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 3 Mercury's Sodium Tail Image Credit & Copyright: Sebastian Voltmer Explanation: That's no comet. Below the Pleiades star cluster is actually a planet: Mercury.Long exposures of our Solar System's innermost planet may reveal something unexpected: a tail.Mercury's thin atmosphere contains small amounts of sodium that glow when excited by light from the Sun.Sunlight also liberates these atoms from Mercury's surface and pushes them away.The yellow glow from sodium, in particular, is relatively bright. Pictured, Mercury and its sodium tail are visible in a deep image taken last week from La Palma, Spainthrough a filter that primarily transmits yellow light emitted by sodium.First predicted in the 1980s, Mercury's tail was first discovered in 2001.Many tail details were revealed in multiple observations by NASA's robotic MESSENGER spacecraft that orbited Mercury between 2011 and 2015. Tails, of course, are usually associated with comets. Tomorrow's picture: planet pyramid parade <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official:...

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Partial Solar Eclipse over Argentina

APOD: 2022 May 2 - Partial Solar Eclipse over Argentina Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 2 Partial Solar Eclipse over Argentina Image Credit & Copyright: Aixa Andrada Explanation: What's happened to the Sun?Two days ago, parts of South America were treated to a partial solar eclipse -- where the Moon blocked out part of the Sun. The featured image shows an image of the partially eclipsed Sun through clouds as it was setting over Patagonia, Argentina.In the tilted image, Earth is toward the right.During the eclipse, the Moon moved partly between Earth and the Sun.Although a visually impressive sight, the slight dimming of surroundings during this partial eclipse was less noticeable than dimming created by a thick cloud.In about two weeks, all of South America and part of North America will experience a total lunar eclipse -- where the Earth moves completely between the Moon and the Sun. In about two years, a total solar eclipse will cross North America. Tomorrow's picture: planet tail <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors:...

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First Horizon Scale Image of a Black Hole

APOD: 2022 May 1 - First Horizon Scale Image of a Black Hole Discover the cosmos!Each day a different image or photograph of our fascinating universe isfeatured, along with a brief explanation written by a professional astronomer. 2022 May 1 First Horizon-Scale Image of a Black Hole Image Credit: Event Horizon Telescope Collaboration Explanation: 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 horizons 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...

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