Ship Tracks over the Pacific Ocean

APOD: 2022 June 8 - Ship Tracks over the Pacific Ocean 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 June 8 Ship Tracks over the Pacific Ocean Image Credit: NASA, Terra, MODIS; Text: Raymond Shaw (MTU) Explanation: What are those unusual streaks?Some images of planet Earth show clear bright streaks that follow the paths of ships. Known as ship tracks, these low and narrow bands are caused by theship's engine exhaust.Water vapor condenses around small bits of exhaust known as aerosols, which soon grow into floating water drops that efficiently reflect sunlight.Ship tracks were first discovered in 1965 in Earth images taken by NASA's TIROS satellites. Multiple ship tracks are visible across the featured image that was captured in 2009 over the Pacific Ocean by the MODIS instrument on NASA's Terra satellite.Inspired by ship-tracks, some scientists have suggested deploying a network of floating buoys in the worlds' oceans that spray salt-aerosol containing sea-water into the air so that, with the help of the wind, streams of sunlight-reflecting clouds would also form. Why do this? These human-made clouds could reflect so much sunlight they might...

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NGC 6188: Dragons of Ara

APOD: 2022 June 7 - NGC 6188: Dragons of Ara 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 June 7 NGC 6188: Dragons of Ara Image Credit & Copyright: Shaun Robertson Explanation: Do dragons fight on the altar of the sky? Although it might appear that way, these dragons are illusions made of thin gas and dust.The emission nebula NGC 6188, home to the glowing clouds, is found about 4,000 light years away near the edge of alarge molecular cloud unseen at visible wavelengths, in the southernconstellationAra (the Altar).Massive, youngstars of the embedded AraOB1 associationwere formed in that region only a few million years ago,sculpting the dark shapes andpowering the nebular glow with stellar winds and intense ultraviolet radiation.The recentstar formation itself was likely triggered bywinds and supernova explosions, from previous generations of massivestars, that swept up and compressed the molecular gas.Joining NGC 6188 on this cosmic canvas, visible toward the lower right, is rare emission nebula NGC 6164,also created by one of the region's massive O-type stars.Similar in appearance to manyplanetary nebulae, NGC 6164's striking,symmetric gaseous shroud and faint halo surround its bright...

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Milky Way Galaxy Doomed: Collision with Andromeda Pending

APOD: 2022 June 6 - Milky Way Galaxy Doomed: Collision with Andromeda Pending 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 June 6 Milky Way Galaxy Doomed: Collision with Andromeda Pending Image Credit: NASA, ESA, Z. Levay and R. van der Marel (STScI); T. Hallas; andA. Mellinger Explanation: Will our Milky Way Galaxy collide one day with its larger neighbor, the Andromeda Galaxy?Most likely, yes. Careful plotting of slight displacements of M31's stars relative to background galaxies on recent Hubble Space Telescope images indicate that the center of M31 could be on a direct collision course with the center of our home galaxy.Still, the errors in sideways velocity appear sufficiently large to admit a good chance that the central parts of the two galaxies will miss, slightly, but will become close enough for their outer halos to become gravitationally entangled.Once that happens, the two galaxies will become bound, dance around, and eventually merge to become one large elliptical galaxy -- over the next few billion years.Pictured here is a combination of images depicting the sky of a world (Earth?) in the distant future when...

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Two Black Holes Dancing in 3C 75

What's happening at the center of active galaxy 3C 75?

Tau Herculids from Space

APOD: 2022 June 4 - Tau Herculids from Space 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 June 4 Tau Herculids from Space Image Credit &Copyright: Zhuoxiao Wang, Yangwang-1 Space Telescope,Origin.Space Explanation: On May 31 tens of parallel meteor streaks were recorded in this8 degree wide field of view of planet Earth's limb from space.The image is one of a series of 5 minute long observationsby the orbitingYangwang-1 space telescope.It was captured at 03:43 UT, near the peak of theTau Herculidmeteor shower.As predicted,the meteor shower was an active one this year,caused as Earth swept through a relativelydense stream of debris fromdisintegratingComet73P/Schwassmann-Wachmann 3,but waslacking bright meteors.Nearly all of the Tau Herculid meteors in the Yangwang-1 image are too faintto be detected by groundbased instruments.But on that datepatient earthboundskywatchers under clear skiesstill enjoyed a memorableshowing of the Tau Herculids. Tomorrow's picture: gravity's dance<| 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.

A 10 000 Kilometer Galactic Bridge

APOD: 2022 June 3 - A 10 000 Kilometer Galactic Bridge 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 June 3 A 10,000 Kilometer Galactic Bridge Image Credit &Copyright: Maxime Oudoux,Jean-Francois GELY Explanation: With this creative astro-collaboration you can follow the plane ofour Milky Way Galaxy as it bridges northern and southernhemisphere skies.To construct the expansive composite nightscape,skies over Observatorio El Sauce in Chile (top)were imaged on the same date but 6 hours later thanthe skies over the Saint-Veran observatory in the French Alps.The 6 hour time-lag allowed Earth's rotation to alignthe Milky Way abovedomes at the two sites.All exposures were made with similar cameras and lenses mounted on simpletripods.A faint greenish airglow is visible in thedark Chilean sky that also features the Largeand Small Magellanic Clouds near the observatory dome.In the French Alps light pollution is apparent,but the distant Andromeda Galaxy can still be spotted near the horizonin the northern night.Onplanet Earththe two observatories are separated by about 10,000 kilometers. Tomorrow's picture: light-weekend<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA...

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Lunar Occultation of Venus

APOD: 2022 June 2 - Lunar Occultation of Venus 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 June 2 Lunar Occultation of Venus Image Credit &Copyright: Quentin Gineys Explanation: On May 27 Venus rose as the morning star, near thewaning crescent Moonin a predawn skyalready full of planets.It was closeon the sky to the Moon's crescent and aconjunction of the second and third brightest celestial beaconswas enjoyed by skygazers around the world.But seen from locations along a track through southeast Asiaand the Indian Oceanthe Moon actually passed in front of Venus ina lunar occultation.In this animated gif the 75 percent illuminated disk ofVenus approachesand just begins to disappear behind the sunlit southwestern lunar limb.The telescopic framesused to construct it were capturedfrom Reunion Island in the Indian Ocean around 4:50am local time,with the Moon and Venus very close to the eastern horizon.At the time Venuswas over 180 million kilometers from Reunion Island,compared to a lunar distance of a mere 400 thousand kilometers or so.About 50 minutes later Venus emerged frombehind the Moon. Tomorrow's picture: pixels in space<| Archive| Submissions | Index| Search| Calendar| RSS| Education|...

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Tau Herculids Meteors over Kitt Peak Telescopes

APOD: 2022 June 1 - Tau Herculids Meteors over Kitt Peak Telescopes 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 June 1 Tau Herculids Meteors over Kitt Peak Telescopes Image Credit & Copyright: Jianwei Lyu (Steward Obs., U. Arizona) Explanation: It wasn't the storm of the century -- but it was a night to remember.Last night was the peak of the Tau Herculids meteor shower, a usually modest dribble of occasional meteors originating from the disintegrating Comet 73P/Schwassmann-Wachmann 3.This year, calculations showed that the Earth might be passing through a particularly dense stream of comet debris -- at best creating a storm of bright meteors streaking out from the constellation of Hercules.What actually happened fell short of a meteor storm, but could be called a decent meteor shower.Featured here is a composite image taken at Kitt Peak National Observatory in Arizona, USA accumulated over 2.5 hours very late on May 30. Over that time, 19 Tau Herculids meteors were captured, along with 4 unrelated meteors. (Can you find them?) In the near foreground is the Bok 2.3-meter Telescope with the 4.0-meter Mayall Telescope just...

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Rocket Transits Rippling Sun

The launch of a rocket at sunrise can result in unusual

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.

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.

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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