Mercury and the Da Vinci Glow

APOD: 2021 July 10 - Mercury and the Da Vinci Glow 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. 2021 July 10 Mercury and the Da Vinci Glow Image Credit &Copyright:Gabriel Funes Explanation: On July 8th early morning risers saw Mercury near an old Moonlow on the eastern horizon.On that datebright planet, faint glow of lunar night side, and sunlit crescentwere captured in this predawn skyscape from Tenerife'sTeide National Park in the Canary Islands. Never far from the Sun in planet Earth's sky, thefleeting inner planetshines near its brightest in the morning twilight scene.Mercury lies just below the zeta star of the constellation Taurus,Zeta Tauri,near thetipof the celestial bull's horn.Of course the Moon's ashen glow is earthshine, earthlight reflectedfrom the Moon's night side.A description of earthshine, in terms of sunlightreflected by Earth's oceans illuminatingthe Moon's dark surface, was written over 500 years ago byLeonardo da Vinci.Waiting for the coming dawn in the foreground are theTeide Observatory'ssentinels of the Sun, also known as (large domes left to right) theTHEMIS,VTT, and GREGOR solar telescopes. Tomorrow's picture: try to see the Moon<| Archive| Submissions | Index| Search| Calendar|...

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M82: Starburst Galaxy with a Superwind

APOD: 2021 July 9 - M82: Starburst Galaxy with a Superwind 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. 2021 July 9 M82: Starburst Galaxy with a Superwind Image Credit &Copyright:Team ARO,Alentejo Remote Observatory Explanation: M82 is a starburst galaxywith a superwind.In fact,through ensuing supernova explosions andpowerful winds from massive stars,the burst of star formation in M82is driving a prodigious outflow.Evidence for the superwindfrom the galaxy's central regionsis clear in sharp telescopic snapshot.The composite image highlights emission fromlong outflow filaments of atomic hydrogen gas in reddish hues.Some of the gas in the superwind,enriched in heavy elementsforged in the massive stars,will eventually escape intointergalactic space.Triggered by aclose encounter withnearby large galaxy M81,the furious burst of star formation in M82 should last about100 million years or so.Also known as the Cigar Galaxy for its elongated visual appearance,M82 is about 30,000 light-years across.It lies 12 million light-years away near the northern boundary ofUrsa Major. Tomorrow's picture: Mercury and the Da Vinci Glow<| 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...

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Perihelion to Aphelion

APOD: 2021 July 8 - Perihelion to Aphelion 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. 2021 July 8 Perihelion to Aphelion Image Credit &Copyright:Richard Jaworski Explanation: Aphelion for 2021 occurred on July 5th.That's the point in Earth's elliptical orbit when it is farthest from the Sun.Of course, the distance from the Sun doesn't determine the seasons.Those are governed bythe tilt of Earth's axis of rotation,so July is still summer in the north and winter in the southernhemisphere.But it does mean that on July 5 the Sun was at its smallestapparent size when viewed from planet Earth.This composite neatly compares two pictures of the Sun,both taken with the same telescope and camera.The left half was captured close to the date of the2021 perihelion (January 2), the closest point in Earth's orbit.The right was recorded just before the aphelion in 2021.Otherwise difficult to notice, the change in theSun's apparent diameter betweenperihelion and aphelionamounts to a little over 3 percent. Tomorrow's picture: starburst and superwind<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip...

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Flight Through the Orion Nebula in Infrared Light

APOD: 2021 July 7 - Flight Through the Orion Nebula in Infrared Light 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. Flight Through the Orion Nebula in Infrared Light Video Credit: NASA, Spitzer Space Telescope, Universe of Learning; Visualization: F. Summers (STScI) et al.; Music & License: Serenade for Strings (A. Dvořák), Advent Chamber Orch. Explanation: What would it look like to fly into the Orion Nebula? The exciting dynamic visualizationof the Orion Nebula is based on real astronomical dataand adept movie rendering techniques.Up close and personal with a famous stellar nurserynormally seenfrom 1,500 light-years away, the digitally modeledrepresentation based is based on infrared data from the Spitzer Space Telescope.The perspective moves along a valley over alight-year wide, in the wall of the region's giant molecular cloud.Orion's valley ends in a cavity carved by the energetic winds and radiation of the massive central stars of theTrapezium star cluster.The entire Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun. Tomorrow's picture: open space <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD|...

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Saturn and Six Moons

APOD: 2021 July 6 - Saturn and Six Moons 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. 2021 July 6 Saturn and Six Moons Image Credit & Copyright: Mohammad Ranjbaran; MR Thanks: Amir Ehteshami Explanation: How many moons does Saturn have?So far 82 have been confirmed, the smallest being only a fractionof a kilometer across.Six of its largest satellites can be seen here in a composite image with 13 short exposure of the bright planet, and13 long exposures of the brightest of its faint moons, taken over two weeks last month. Larger than Earth's Moon and even slightly larger than Mercury,Saturn's largest moonTitan has a diameter of 5,150 kilometers and was captured making nearly a complete orbit around its ringed parent planet. Saturn's first known natural satellite, Titan wasdiscovered in 1655 byDutch astronomer Christiaan Huygens, in contrast with several newly discovered moons announced in 2019. The trail on the far right belongs to Iapetus, Saturn's third largest moon.The radius of painted Iapetus' orbit is so large that only a portion of it was captured here.Saturn leads Jupiter across the night sky this month, rising soon...

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IC 4592: The Blue Horsehead Reflection Nebula

Do you see the horse's head?

The Face on Mars

APOD: 2021 July 4 - The Face on Mars 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. 2021 July 4 The Face on Mars Image Credit: NASA, Viking 1 Orbiter Explanation: Wouldn't it be fun if clouds were castles? Wouldn't it be fun if the laundry on the bedroom chair was a superhero? Wouldn't it be fun if rock mesas on Mars were interplanetary monuments to the human face? Clouds, though, are floating droplets of water and ice. Laundry is cotton, wool, or plastic, woven into garments. Famous Martian rock mesas known by names like the Face on Mars appear quite natural when seen more clearly on better images. Is reality boring?Nobody knows why some clouds make rain. Nobody knows if life ever developed on Mars. Nobody knows why the laundry on the bedroom chair smells like root beer. Scientific exploration can not only resolve mysteries, but uncover new knowledge, greater mysteries, and yet deeper questions. As humanity explores our universe, perhaps fun -- through discovery -- is just beginning. Tomorrow's picture: horse of blue <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About...

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Along the Milky Way

APOD: 2021 July 3 - Along the Milky Way 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. 2021 July 3 Along the Milky Way Image Credit &Copyright:Rolf Weisenfeld Explanation: You can'twalk along the Milky Way.Still, under a dark skyyou can explore it.To the eye the pale luminous trail of light arcingthrough the sky on a dark, moonless night does appear to bea path through the heavens.The glowing celestial band is the faint,collectivelight of distant starscut by swaths of obscuring interstellar dust clouds.It lies along the plane ofour home galaxy,so named because it looks like a milky way.Since Galileo's time, the Milky Way has been revealedto telescopic skygazers to be filled withcongeries of innumerable starsandcosmic wonders. Tomorrow's picture: Facing Mars<| 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.

AR2835: Islands in the Photosphere

APOD: 2021 July 2 - AR2835: Islands in the Photosphere 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. 2021 July 2 AR2835: Islands in the Photosphere Image Credit &Copyright:MichaelTeoh,Heng Ee Observatory, Penang, Malaysia Explanation: Awash in a sea ofincandescent plasmaand anchored in strongmagnetic fields,sunspots are planet-sized dark islands inthe solar photosphere,the bright surface of the Sun.Found in solar active regions, sunspots lookdarkonly because they are slightly cooler though,with temperatures of about 4,000kelvinscompared to 6,000 kelvins for the surrounding solar surface.These sunspots lie in active region AR2835.The largest active regionnow crossing the Sun,AR2835 is captured in this sharp telescopic close-up from July 1in a field of view that spans about 150,000 kilometersor over ten Earth diameters.With powerful magnetic fields,solar active regionsare often responsible for solar flares and coronal mass ejections, storms which affectspace weathernearplanet Earth. Tomorrow's picture: Got telescope?<| 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.

Perseverance Selfie with Ingenuity

APOD: 2021 July 1 - Perseverance Selfie with Ingenuity 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. 2021 July 1 Perseverance Selfie with Ingenuity Image Credit: NASA,JPL-Caltech,MSSS Explanation: On sol 46 (April 6, 2021) the Perseverance rover held out arobotic arm to takeits first selfie on Mars.The WATSON camera at the end of the armwas designed to take close-ups of martian rocks andsurface details though, and not a quick snap shot of friends andsmiling faces.In the end,teamworkand weeks of planning on Mars timewas required to program a complex series ofexposures and camera motions to include Perseverance and itssurroundings.The resulting 62 frames were composed into a detailed mosiac,one of the most complicated Mars rover selfies ever taken.In this version of theselfie, the rover'sMastcam-Z and SuperCam instruments are lookingtoward WATSON and the end of the rover's outstretched arm.About 4 meters (13 feet) from Perseverance is a robotic companion,the Mars Ingenuity helicopter. 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...

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Simulation: Formation of the First Stars

APOD: 2021 June 30 - Simulation: Formation of the First Stars 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: Formation of the First Stars Video Credit: Harley Katz (U. Oxford) et al. Explanation: How did the first stars form?To help find out, the SPHINX computer simulation of star formation in the very early universe was created, some results of which are shown in the featured video.Time since the Big Bang is shown in millions of years on the upper left. Even 100 million years after the Big Bang, matter was spread too uniformly across the cosmos for stars to be born. Besides background radiation, the universe was dark.Soon, slight matter clumps rich in hydrogen gas begin to coalesce into the first stars.In the time-lapse video, purple denotes gas, white denotes light, and gold shows radiation so energetic that it ionizes hydrogen, breaking it up into charged electrons and protons. The gold-colored regions also track the most massive stars that die with powerful supernovas.The inset circle highlights a central region that is becoming a galaxy. The simulation continues until the universe was about 550 million...

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Orion Nebula: The Hubble View

APOD: 2021 June 29 - Orion Nebula: The Hubble View 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. 2021 June 29 Orion Nebula: The Hubble View Image Credit: NASA, ESA, Hubble Legacy Archive; Processing: Francisco Javier Pobes Serrano Explanation: Few cosmic vistas excite the imagination likethe Orion Nebula.Also known asM42,the nebula's glowing gas surrounds hot young stars at the edge of animmense interstellarmolecular cloud only 1,500 light-years away.The Orion Nebula offers one of the best opportunities to study how stars are born partly because it is the nearest largestar-forming region,but also because the nebula'senergetic stars have blown away obscuring gas and dust clouds that would otherwise block our view - providing an intimate look at a range of ongoing stagesof starbirth and evolution.The featured image of theOrion Nebula is among the sharpest ever, constructed using data from theHubble Space Telescope. The entire Orion Nebula spans about 40 light years and is located in the same spiral arm of our Galaxy as the Sun. Tomorrow's picture: first stars <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU)...

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A Paper Moon Solar Eclipse

APOD: 2021 June 28 - A Paper Moon Solar 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. 2021 June 28 A Paper Moon Solar Eclipse Image Credit & Copyright: Wang Letian (Eyes at Night) Explanation: It may look like a paper Moon. Sailing past a canvas Sun. But those are not cardboard clouds. And it's not make believe. The featured picture of an orange colored sky is real -- a digital composite of two exposures of the solar eclipse that occurred earlier this month. The first exposure was taken with a regular telescope that captured an overexposed Sun and an underexposed Moon, while the second image was taken with a solar telescope that captured details of the chromosphere of the background Sun.The Sun's canvas-like texture was brought up by imaging in a very specific shade of red emitted by hydrogen. Several prominences can be seen around the Sun's edge. The image was captured just before sunset from Xilingol, Inner Mongolia, China.It's also not make-believe to imagine that the Moon is made of dense rock, the Sun is made of hot gas, and clouds are made...

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A Paper Moon Solar Eclipse

Astronomy Picture of the Day 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. 2021 June 28 A Paper Moon Solar Eclipse Image Credit & Copyright: Wang Letian (Eyes at Night) Explanation: It may look like a paper Moon. Sailing past a canvas Sun. But those are not cardboard clouds. And it's not make believe. The featured picture of an orange colored sky is real -- a digital composite of two exposures of the solar eclipse that occurred earlier this month. The first exposure was taken with a regular telescope that captured an overexposed Sun and an underexposed Moon, while the second image was taken with a solar telescope that captured details of the chromosphere of the background Sun.The Sun's canvas-like texture was brought up by imaging in a very specific shade of red emitted by hydrogen. Several prominences can be seen around the Sun's edge. The image was captured just before sunset from Xilingol, Inner Mongolia, China.It's also not make-believe to imagine that the Moon is made of dense rock, the Sun is made of hot gas, and clouds are made of floating droplets of water...

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The Dancing Auroras of Saturn

APOD: 2021 June 27 - The Dancing Auroras of 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. 2021 June 27 The Dancing Auroras of Saturn Image Credit: NASA,Cassini,VIMS Team,U. Arizona, U. Leicester, JPL, ASI Explanation: What drives auroras on Saturn?To help find out, scientists have sorted through hundreds of infrared images of Saturn taken by the Cassini spacecraft for other purposes, trying to find enough aurora images to correlate changes and make movies.Once made, some movies clearly show that Saturnian auroras can change not only with the angle of the Sun, but also as the planet rotates.Furthermore, some auroral changes appear related to waves in Saturn's magnetosphere likely caused by Saturn's moons.Pictured here, a false-colored image taken in 2007 shows Saturn in three bands of infrared light. The rings reflect relatively blue sunlight, while the planet itself glows in comparatively low energy red. A band of southern aurora in visible in green.In has recently been found that auroras heat Saturn's upper atmosphere.Understanding Saturn's auroras is a path toward a better understanding of Earth's auroras. Tomorrow's picture: paper moon eclipse <| Archive| Submissions | Index|...

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