Pleiades over Half Dome

APOD: 2022 July 19 - Pleiades over Half Dome 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 July 19 Pleiades over Half Dome Image Credit & Copyright: Dheera Venkatraman Explanation: Stars come in bunches. The most famous bunch of stars on the sky is the Pleiades, a bright cluster that can be easily seen with the unaided eye. The Pleiades lies only about 450 light years away, formed about 100 million years ago, and will likely last about another 250 million years.Our Sun was likely born in a star cluster, but now, being about 4.5 billion years old, its stellar birth companions have long since dispersed.The Pleiades star cluster is pictured over Half Dome, a famous rock structure in Yosemite National Park in California, USA.The featured image is a composite of 28 foreground exposures and 174 images of the stellar background, all taken from the same location and by the same camera on the same night in October 2019.After calculating the timing of a future juxtaposition of the Pleiades and Half Dome, the astrophotrographer was unexpectedly rewarded by an electrical blackout, making the background...

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Stephans Quintet from Webb, Hubble, and Subaru

APOD: 2022 July 18 - Stephans Quintet from Webb, Hubble, and Subaru 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 July 18 Stephan's Quintet from Webb, Hubble, and Subaru Image Credit: Webb, Hubble, Subaru;NASA, ESA, CSA,NOAJ,STScI; Processing & Copyright: Robert Gendler Explanation: OK, but why can't you combine images from Webb and Hubble?You can, and today's featured image shows one impressive result.Although the recently launched James Webb Space Telescope (Webb) has a larger mirror than Hubble, it specializes in infrared light and can't see blue -- only up to about orange. Conversely, the Hubble Space Telescope (Hubble) has a smaller mirror than Webb and can't see as far into the infrared as Webb, but can image not only blue light but even ultraviolet. Therefore, Webb and Hubble data can be combined to create images across a wider variety of colors. The featured image of four galaxies from Stephan's Quintet shows Webb images as red and also includes images taken by Japan's ground-based Subaru telescope in Hawaii. Because image data for Webb, Hubble, and Subaru are made freely available, anyone around the world can process...

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Europa and Jupiter from Voyager 1

APOD: 2022 July 17 - Europa and Jupiter from Voyager 1 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 July 17 Europa and Jupiter from Voyager 1 Image Credit: NASA, Voyager 1, JPL, Caltech; Processing & License: Alexis Tranchandon / Solaris Explanation: What are those spots on Jupiter?Largest and furthest, just right of center, is the Great Red Spot -- a huge storm system that has been raging on Jupiter possibly since Giovanni Cassini's likely notation of it 357 years ago. It is not yet known why this Great Spot is red.The spot toward the lower left is one of Jupiter's largest moons: Europa.Images from Voyager in 1979 bolster the modern hypothesis that Europa has an underground ocean and is therefore a good place to look for extraterrestrial life.But what about the dark spot on the upper right?That is a shadow of another of Jupiter's large moons: Io.Voyager 1 discovered Io to be so volcanic that no impact craters could be found. Sixteen frames from Voyager 1's flyby of Jupiter in 1979 were recently reprocessed and merged to create the featured image. Forty-five years...

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Tycho and Clavius at Dawn

APOD: 2022 July 16 - Tycho and Clavius at Dawn 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 July 16 Tycho and Clavius at Dawn Image Credit &Copyright:EduardoSchaberger Poupeau Explanation: South is upin this dramatic telescopic view of thelunar terminatorand the Moon's rugged southern highlands.The lunar landscape was captured on July 7with the moon at itsfirst quarter phase.The Sun shines at a low angle from the rightas dawn comes to the region's young and old cratersTycho and Clavius.About 100 million years young,Tycho isthe sharp-walled 85 kilometer diameter crater below and left of center.Its 2 kilometer tall central peak and far crater wall reflectbright sunlight,Its smooth floor lies in dark shadow.Debris ejected during the impact that created Tycho make it thestandout lunar crater when theMoon is near full though.They produce a highly visible radiating system of light streaks orrays that extend across much of the lunar near side.In fact, some of the material collected at the Apollo 17 landing site,about 2,000 kilometers away, likely originatedfrom the Tycho impact. One of the oldest and largest craters on the Moon's near side,225 kilometer diameterClavius is due south(above)...

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Lubovna Full Moon

APOD: 2022 July 15 - Lubovna Full 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 July 15 Lubovna Full Moon Petr Horalek /Institute of Physics in Opava Explanation: On July 13 this well-planned telephoto view recorded a Full Moonrising overLubovna Castle in eastern Slovakia.The photographer was about 3 kilometers from the castle walls andabout 357,000 kilometers from thisFull Moon near perigee, the closestpoint in its elliptical orbit.Known to some as supermoons, full moons near perigeeare a little brighter andlarger in planet Earth's sky whencompared to full moons that occur near theaverage lunar distanceof around 384,000 kilometers.Of course anyFull Moon near the horizoncan show the effects ofrefraction over a long sight-line through dense clear atmosphere.In this image, atmospheric refraction creates the slight green flashframed by thin clouds near the top, with a raggedred rim along the bottom edge ofJuly's perigee Full Moon. Tomorrow's picture: Clavius and Tycho<| 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.

Webb's Southern Ring Nebula

APOD: 2022 July 14 - Webb's Southern Ring 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 July 14 Webb's Southern Ring Nebula Image Credit: NASA,ESA,CSA,STScI,NIRCam Explanation: Cataloged as NGC 3132the Southern Ring Nebula is aplanetary nebula,the death shroud of adying sun-like star some 2,500 light-years from Earth.Composed of gas and dust the stunningcosmic landscape is nearly halfa light-year in diameter, explored inunprecedented detail by theJames Webb Space Telescope.In this NIRCam image the bright star near centeris a companion of the dying star.In mutual orbit, the star whose transformation has ejectedthe nebula's gas and dust shells over thousands of yearsis the fainter stellar partner.Evolving to become a white dwarf,the faint star appears along thediffraction spike extending towardthe 8 o'clock position.This stellar pair's orbital motion has resulted thecomplex structures within the Southern Ring Nebula. Tomorrow's picture: Clavius and Tycho<| 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.

Webb s First Deep Field

APOD: 2022 July 13 - Webb s First Deep Field 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 July 13 Webb's First Deep Field Image Credit: NASA,ESA,CSA,STScI,NIRCam Explanation: This is the deepest,sharpest infrared image of the cosmos so far.The viewof theearly Universetoward the southern constellation Volanswas achieved in 12.5 hours of exposure with the NIRCam instrument on theJames Webb Space Telescope.Of course the stars with six visible spikes are well within our ownMilky Way.Their diffractionpattern is characteristic of Webb's 18 hexagonal mirrorsegments operating together as a single 6.5 meter diameter primarymirror.The thousands of galaxies flooding the field of view are members of thedistant galaxy cluster SMACS0723-73, some 4.6 billion light-years away.Luminous arcs that seem to infest the deep field areeven more distant galaxies though.Their images are distorted and magnified by thedark matter dominated mass of the galaxy cluster, an effectknown as gravitational lensing.Analyzing lightfrom two separate arcs below the bright spiky star,Webb's NIRISS instrument indicates the arcsare both images of the same background galaxy.And that galaxy's light took about 9.5 billion years to reach theJames Webb Space Telescope. Tomorrow's picture: closer to home<| Archive|...

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Noctilucent Clouds over Paris

It's northern noctilucent cloud season.

Andromeda over the Sahara Desert

APOD: 2022 July 11 - Andromeda over the Sahara Desert 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 July 11 Andromeda over the Sahara Desert Credit & Copyright: Jordi Coy Explanation: What is the oldest thing you can see?At 2.5 million light years distant, the answer for the unaided eye is the Andromeda galaxy, because its photons are 2.5 million years old when they reach you.Most other apparent denizens of the night sky -- stars, clusters, and nebulae -- appear as they were only a few hundred to a few thousand years ago, as they lie well within our own Milky Way Galaxy. Given its distance, light from Andromeda is likely also the farthest object that you can see. Also known as M31, the Andromeda Galaxy dominates the center of the featured zoomed image, taken from the Sahara Desert in Morocco last month. The featured image is a combination of three background and one foreground exposure -- all taken with the same camera and from the same location and on the same calendar day -- with the foreground image taken during the evening blue...

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In the Center of the Cats Eye Nebula

APOD: 2022 July 10 - In the Center of the Cats Eye 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 July 10 In the Center of the Cat's Eye Nebula Credit: NASA, ESA, Hubble, HLA; Reprocessing & Copyright: Raul Villaverde Explanation: Three thousand light-years away,a dying star throws off shells of glowing gas.This image from theHubble Space Telescope reveals theCat's Eye Nebula (NGC 6543), to be one of the most complex planetary nebulae known.Spanning half a light-year, the features seen in theCat's Eyeare so complex that astronomers suspect the brightcentral objectmay actually be abinary star system.The term planetary nebula, used to describe thisgeneral class of objects, ismisleading.Although these objects may appear round andplanet-like in small telescopes,high resolution images with large telescopes reveal them to bestars surrounded by cocoons of gas blown off in the late stages ofstellar evolution.Gazing into this Cat's Eye,astronomers may well be seeing more than detailed structure,they may be seeing the fate of our Sun, destined to enter its ownplanetary nebula phase of evolution ... in about5 billion years. Tomorrow's picture: sahara andromeda <| Archive| Submissions | Index| Search| Calendar|...

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Saturn and ISS

Soaring high in skies around planet Earth, bright planet

Roots on a Rotating Planet

With roots on a

The NGC 6914 Complex

APOD: 2022 July 7 - The NGC 6914 Complex 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 July 7 The NGC 6914 Complex Image Credit &Copyright: Giorgio Ferrari Explanation: A study in contrasts,this colorful skyscapefeaturesstars, dust, and glowing gasin the vicinity of NGC 6914.Theinterstellar complex of nebulaelies some 6,000 light-years away,toward the high-flying northern constellationCygnus and the plane of ourMilky Way Galaxy.Obscuring interstellar dust clouds appear insilhouette while reddish hydrogenemission nebulae,along with the dusty bluereflection nebulae,fill the cosmic canvas.Ultraviolet radiation from the massive, hot, young stars of the extensiveCygnus OB2association ionize the region's atomichydrogen gas, producingthe characteristic red glow as protons and electrons recombine.Embedded Cygnus OB2 stars also provide theblue starlight strongly reflected by the dust clouds.The over 1 degree wide telescopic field of view spansabout 100 light-years at the estimated distance of NGC 6914. Tomorrow's picture: star treels<| 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.

Milky Way Motion in 3D from Gaia

Our sky is alive with the streams of stars.

A Molten Galaxy Einstein Ring Galaxy

APOD: 2022 July 5 - A Molten Galaxy Einstein Ring Galaxy 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 July 5 A Molten Galaxy Einstein Ring Image Credit: ESA/Hubble & NASA, S. Jha; Processing: Jonathan Lodge Explanation: It is difficult to hide a galaxy behind a cluster of galaxies. The closer cluster's gravity will act like a huge lens, pulling images of the distant galaxy around the sides and greatly distorting them. This is just the case observed in the featured image recently re-processed image from the Hubble Space Telescope. The cluster GAL-CLUS-022058c is composed of many galaxies and is lensing the image of a yellow-red background galaxy into arcs seen around the image center. Dubbed a molten Einstein ring for its unusual shape, four images of the same background galaxy have been identified.Typically, a foreground galaxy cluster can only create such smooth arcs if most of its mass is smoothly distributed -- and therefore not concentrated in the cluster galaxies visible. Analyzing the positions of these gravitational arcs gives astronomers a method to estimate the dark matter distribution in galaxy clusters, as well...

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