Red Crepuscular Rays from an Eclipse

APOD: 2022 May 30 - Red Crepuscular Rays from an 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 30 Red Crepuscular Rays from an Eclipse Image Credit & Copyright: Fefo Bouvier Explanation: What's happening behind that island?Things both expected and unexpected.Expected, perhaps, the pictured rays of light -- called crepuscular rays -- originate from the Sun.Unexpected, though, the Sun was being partially eclipsed by the Moon at the time -- late last month.Expected, perhaps, the Sun's rays are quite bright as they shine through gaps in below-horizon clouds.Unexpected, though, the crepuscular rays are quite red, likely the result an abundance of aerosols in Earth's atmosphere scattering away much of the blue light. Expected, with hope, a memorable scene featuring both the Moon and the Sun, superposed.Unfortunately, from this location -- in Uruguay looking toward Argentina -- clouds obscured the eclipse -- which wasn't completely unexpected. However, after packing up to go home, the beauty of bright red crepuscular rays emerged -- quite unexpectedly. Oh -- and that island on the horizon -- it's really two islands. Tomorrow's picture: yellow liquid sun <|...

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Simulation TNG50: A Galaxy Cluster Forms

APOD: 2022 May 29 - Simulation TNG50: A Galaxy Cluster Forms 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. Simulation TNG50: A Galaxy Cluster Forms Video Credit: IllustrisTNG Project;Visualization: Dylan Nelson (Max Planck Institute for Astrophysics) et al. Music: Symphony No. 5 (Ludwig van Beethoven), via YouTube Audio Library Explanation: How do clusters of galaxies form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out.A recent effort is TNG50 from IllustrisTNG, an upgrade of the famous Illustris Simulation.The first part of the featured video tracks cosmic gas (mostly hydrogen) as it evolves into galaxies and galaxy clusters from the early universe to today, with brighter colors marking faster moving gas. As the universe matures, gas falls into gravitational wells, galaxies forms, galaxies spin, galaxies collide and merge, all while black holes form in galaxy centers and expel surrounding gas at high speeds.The second half of the video switches to tracking stars, showing a galaxy cluster coming together complete with tidal tails and stellar streams.The outflow from black holes in TNG50 is surprisingly complex and details are being...

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RCW 86: Historical Supernova Remnant

APOD: 2022 May 28 - RCW 86: Historical Supernova Remnant 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 28 RCW 86: Historical Supernova Remnant Image Credit &Copyright: Martin Pugh Explanation: In 185 AD,Chinese astronomersrecorded the appearance of a new star in the Nanmen asterism.That part of the sky isidentified with Alpha and Beta Centauri on modern star charts.The new star was visible for months and is thought to be the earliestrecorded supernova.This deep image shows emission nebula RCW 86,understood to be the remnant of that stellar explosion.The narrowband data trace gas ionized by the stillexpanding shock wave.Space-based imagesindicate an abundance of the element ironand lack of a neutron star or pulsarin the remnant,suggesting that the original supernova was Type Ia.Unlike the core collapsesupernova explosion of a massive star, aType Ia supernovais a thermonucleardetonation on a a white dwarfstar that accretes material from a companion in a binary star system.Near the plane of ourMilky Waygalaxy and larger than a full moon on the sky this supernova remnantis too faint to be seen by eye though.RCW 86 is some 8,000 light-years distant and around 100...

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Titan: Moon over Saturn

APOD: 2022 May 27 - Titan: Moon over Saturn 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 27 Titan: Moon over Saturn Image Credit: NASA,JPL-Caltech, Space ScienceInstitute Explanation: Like Earth's moon,Saturn's largest moon Titanis locked in synchronous rotation.This mosaicof images recorded by the Cassini spacecraft in May of 2012shows its anti-Saturn side, the sidealways facing away from theringed gas giant.The only moon in the solar system with a dense atmosphere,Titan is the onlysolar system world besides Earth known tohave standing bodies of liquid on its surface and an earthlikecycle of liquid rain and evaporation.Its high altitude layer of atmospheric haze is evident in the Cassiniview of the 5,000 kilometer diameter moon over Saturn's rings and cloudtops.Near centeris the dark dune-filled region known asShangri-La.The Cassini-delivered Huygens probe rests below and left of center,after the most distant landingfor a spacecraft from Earth. Tomorrow's picture: light-weekend<| 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 4565: Galaxy on Edge

APOD: 2022 May 26 - NGC 4565: Galaxy on Edge 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 26 NGC 4565: Galaxy on Edge Image Credit &Copyright:Michael Sherick Explanation: Magnificent spiral galaxyNGC 4565is viewed edge-on from planet Earth.Also known as the Needle Galaxy for its narrow profile,bright NGC 4565 is a stop on many telescopic tours of the northern sky,in the faint but well-groomedconstellation ComaBerenices.This sharp, colorful imagereveals the galaxy'sboxy, bulgingcentral core cut byobscuring dust lanes that laceNGC 4565's thin galactic plane.NGC 4565 itself lies about 40 million light-years distant and spanssome 100,000 light-years. Easily spotted with small telescopes,skyenthusiasts consider NGC 4565 to be a prominent celestialmasterpiece Messier missed. 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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The Lively Center of the Lagoon Nebula

APOD: 2022 May 25 - The Lively Center of the Lagoon 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 25 The Lively Center of the Lagoon Nebula Image Credit: NASA, ESA, Hubble; Processing & Copyright: Mehmet Hakan Özsaraç Explanation: 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 10 light years, combines images taken in six 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). Almost hyperspace: Random APOD Generator Tomorrow's picture: open space <| Archive| Submissions | Index|...

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A Deep Sky Behind an Eclipsed Moon

The plan was to capture a picturesque part of the sky that was hosting an unusual guest.

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The Once and Future Stars of Andromeda

APOD: 2022 May 23 - The Once and Future Stars of Andromeda 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 23 The Once and Future Stars of Andromeda Image Credit: NASA, NSF, NOAJ, Hubble, Subaru, Mayall, DSS, Spitzer; Processing & Copyright: Robert Gendler & Russell Croman Explanation: This picture of Andromeda shows not only where stars are now, but where stars will soon be.Of course, the big, beautiful Andromeda Galaxy, M31, is a spiral galaxy -- and a mere 2.5 million light-years away. Both space-based and ground-based observatories have been here combined to produce this intriguing composite image of Andromeda, at wavelengths both inside and outside normally visible light.The visible light shows where M31's stars are now -- as highlighted in white and blue hues and imaged by the Hubble, Subaru, and Mayall telescopes. The infrared light shows where M31's future stars will soon form -- as highlighted in orange hues and imaged by NASA's Spitzer Space Telescope. The infrared light tracks enormous lanes of dust, warmed by stars, sweeping along Andromeda's spiral arms. This dust is a tracer of the galaxy's vast...

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A Large Tsunami Shock Wave on the Sun

APOD: 2022 May 22 - A Large Tsunami Shock Wave on 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. 2022 May 22 A Large Tsunami Shock Wave on the Sun Image Credit: NSO/AURA/NSF andUSAF Research Laboratory Explanation: Tsunamis this large don't happen on Earth. During 2006, a large solar flare from an Earth-sizedsunspot produced atsunami-typeshock wave that was spectacular even for the Sun. Pictured here, thetsunami wave was captured moving out from active region AR 10930 by the Optical Solar Patrol Network(OSPAN) telescope inNew Mexico,USA. The resultingshock wave, known technically as aMoreton wave, compressed and heated up gasses includinghydrogen in thephotosphereof the Sun, causing a momentarily brighter glow. The featured image was taken in avery specific red coloremitted exclusively by hydrogen gas. The rampaging tsunami took out some active filaments on the Sun,although many re-established themselves later. The solar tsunami spread at nearly one million kilometers per hour,and circled the entireSun in a matter of minutes. Tomorrow's picture: andromeda now and again <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA...

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Planetary Nebula Abell 7

APOD: 2022 May 21 - Planetary Nebula Abell 7 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 21 Planetary Nebula Abell 7 Image Credit &Copyright:Donald Waid,Ron Dilulio Explanation: Very faint planetary nebula Abell 7 is some 1,800 light-years distant,just south of Orion in planet Earth's skies in the constellationLepus, The Hare.Surrounded by Milky Way stars and near the line-of-sight todistant background galaxies, itsgenerallysimple spherical shape, about 8 light-years in diameter, is outlined inthis deep telescopic image.Within its confines are beautiful, more complex details enhancedby the use of narrowband filters.Emission from hydrogen is shown in reddish hues with oxygenemission mapped to green and blue colors, giving Abell 7 a naturalappearance that would otherwise be much too faint to be appreciatedby eye.A planetarynebula represents a very brief final phasein stellar evolution that our own Sun will experience 5 billionyears hence,as the nebula's central, once sun-like starshrugs off its outer layers.Abell 7 itself is estimated to be 20,000 years old.Its central star is seen here as afading white dwarfsome 10 billion years old. Tomorrow's picture: Tsunami on the Sun<| Archive| Submissions | Index| Search| Calendar| RSS|...

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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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