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. 2023 May 13 Apollo 17: The Crescent Earth Image Credit: Apollo 17,NASA;Restoration -Toby Ord Explanation: Our fair planetsports a curved, sunlit crescentagainst the black backdrop of space in this stunning photograph.From the unfamiliar perspective,the Earth is smalland, like atelescopic image of a distant planet,the entire horizon is completely within the field of view.Enjoyed bycrews on boardthe International Space Station,only much closer views of the planet are possible from low Earth orbit.Orbiting the planet once every 90 minutes, a spectacle of clouds, oceans,and continentsscrolls beneath themwith the partial arc of the planet's edge in the distance.But this digitally restored imagepresents a view so faronly achieved by 24 humans,Apollo astronautswho traveled to the Moon and back again between 1968 and 1972.The original photograph,AS17-152-23420,was taken by the homeward bound crew ofApollo 17, on December 17, 1972.For now it is the last picture of Earth from thisplanetary perspective taken by human hands. Tomorrow's picture: free space<| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA...

APOD: 2023 May 11 - Fomalhaut's Dusty Debris Disk 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. 2023 May 11 Fomalhaut's Dusty Debris Disk Image Credit: NASA,ESA,CSA,Processing: András Gáspár (Univ. of Arizona),Alyssa Pagan (STScI),Science: A. Gáspár (Univ. of Arizona) et al. Explanation: Fomalhautis a bright star, a 25 light-yearvoyagefrom planet Earth in the directionof the constellationPiscisAustrinus.Astronomers firstnoticedFomalhaut's excess infrared emission in the 1980s.Space and ground-based telescopeshave sinceidentified the infrared emission's source as a disk of dusty debris,evidence fora planetary system surrounding the hot, young star. But this sharp infrared imagefrom the James Webb Space Telescope's MIRI camerareveals details of Fomalhaut's debris disk never before seen,including a large dust cloud in the outer ring that is possibleevidence for colliding bodies,andan inner dust disk and gap likely shaped andmaintained by embedded but unseen planets.An image scale bar in auor astronomical units, the average Earth-Sun distance,appears at the lower left.Fomalhaut's outer circumstellar dust ring liesat about twice the distance of our own Solar System'sKuiper Belt ofsmall icy bodies and debris beyond the orbit of Neptune. Tomorrow's picture: Halley dust <| Archive| Submissions | Index| Search| Calendar| RSS| Education|...

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. 2023 May 12 Halley Dust, Mars Dust, and Milky Way Image Credit &Copyright:Petr Horalek /Institute of Physics in Opava Explanation: Grains of cosmic duststreaked through night skies in early May.Swept up as planet Earth plowed through thedebris streams left behind byperiodic Comet Halley,the annual meteor shower is known as the Eta Aquarids.This year, the Eta Aquarids peak was visually hampered byMay's bright Full Moon, though.But early morning hours surrounding last May's shower of Halley dust werefree of moonlight interference.In exposures recorded betweenApril 28 and May 8 in 2022,this composited imageshows nearly 90 Eta Aquarid meteors streaking from the shower'sradiant in Aquarius over San Pedro de Atacama, Chile.The central Milky Way arcs above inthe southern hemisphere's predawn skies.The faint band of light rising from the horizon is Zodiacal light,caused by dust scattering sunlight near our Solar System's ecliptic plane.Along the ecliptic and entrained in the Zodiacal gloware the bright planetsVenus, Jupiter, Mars, and Saturn. Of course Mars itselfhas recently been found to be a likely sourceof the dust along the ecliptic responsible for...

APOD: 2023 May 5 - Shackleton from ShadowCam 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. 2023 May 5 Shackleton from ShadowCam Image Credit:NASA,ShadowCam,Korea Aerospace Research Institute,Arizona State University Explanation: Shackleton crater lies atthe lunar south pole.Peaks along its 21 kilometer diameterare in sunlight, but Shackleton's floor is indark permanent shadow.Still, this image of the shadowed rim wall and floorof Shackleton crater wascaptured from NASA's ShadowCam,an instrument on board the Korea Pathfinder Lunar Orbiter(KPLO) launched in August 2022.About 200 times more sensitive than, for example, the LunarReconnaissance Orbiter's Narrow Angle Camera,ShadowCam was designed toimage the permanently shadowed regions of the lunar surface.Avoiding direct sunlight, those regions are expected to bereservoirs of water-iceand other volatiles deposited by ancient cometary impacts anduseful to future Moon missions.Of course, the permanently shadowed regions arestill illuminated by reflections of sunlight fromnearby lunar terrain.In this stunninglydetailed ShadowCam image,an arrow marks the track made by a single boulder rolling downShackleton crater's wall.The image scale is indicated at the bottom of the frame. Tomorrow's picture: twilight in a flower <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors...

Twilight in a Flower

APOD: 2023 May 4 - The Galaxy, the Jet, and a Famous 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. 2023 May 4 The Galaxy, the Jet, and a Famous Black Hole Image Credit:NASA,JPL-Caltech,Event Horizon Telescope Collaboration Explanation: Bright elliptical galaxy Messier 87 (M87)is home to thesupermassive black hole captured in 2017 by planet Earth'sEvent Horizon Telescopein the first ever image of a black hole.Giant of the Virgo galaxy cluster about 55 million light-years away,M87 is the large galaxy rendered in blue hues in this infraredimagefrom the Spitzer Space telescope. Though M87 appears mostly featureless and cloud-like,the Spitzer image does record details of relativisticjets blasting from the galaxy's central region.Shown in the inset at top right, the jets themselvesspan thousands of light-years.The brighter jet seen on theright is approaching and close to our line of sight.Opposite, the shock created by the otherwise unseen receding jetlights up a fainter arc of material.Inset at bottom right, thehistoric black hole image is shownin context, at the center of giant galaxy and relativistic jets.Completely unresolved in the Spitzer image, thesupermassiveblack hole surrounded by infalling material is the...

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. 2023 May 5 Shackleton from ShadowCam Image Credit:NASA,ShadowCam,Korea Aerospace Research Institute,Arizona State University Explanation: Shackleton crater lies atthe lunar south pole.Peaks along the 21 kilometer diameterare in sunlight, but Shackleton's floor is indark permanent shadow.Still, this image of the shadowed rim wall and floorof Shackleton crater wascaptured from NASA's ShadowCam,an instrument on board the Korea Pathfinder Lunar Orbiter(KPLO) launched in August 2022.About 200 times more sensitive than, for example, the LunarReconnaissance Orbiter's Narrow Angle Camera,ShadowCam was designedimage the permanently shadowed regions of the lunar surface.Avoiding direct sunlight, those regions are expected to bereservoirs of water-iceand other volatiles deposited by ancient cometary impacts anduseful to future Moon missions.Of course, the permanently shadowed regions arestill illuminated by reflections of sunlight fromnearby lunar terrain.In this stunninglydetailed ShadowCam image,an arrow marks the track made by a single boulder rolling downShackleton crater's wall.The image scale is indicated at the bottom of the frame. Tomorrow's picture: twilight in a flower <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU)...

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. 2023 May 4 The Galaxy, the Jet, and a Famous Black Hole Image Credit:NASA,JPL-Caltech,Event Horizon Telescope Collaboration Explanation: Bright elliptical galaxy Messier 87 (M87)is home to thesupermassive black hole captured in 2017 by planet Earth'sEvent Horizon Telescopein the first ever image of a black hole.Giant of the Virgo galaxy cluster about 55 million light-years away,M87 is the large galaxy rendered in blue hues in this infraredimagefrom the Spitzer Space telescope. Though M87 appears mostly featureless and cloud-like,the Spitzer image does record details of relativisticjets blasting from the galaxy's central region.Shown in the inset at top right, the jets themselvesspan thousands of light-years.The brighter jet seen on theright is approaching and close to our line of sight.Opposite, the shock created by the otherwise unseen receding jetlights up a fainter arc of material.Inset at bottom right, thehistoric black hole image is shownin context, at the center of giant galaxy and relativistic jets.Completely unresolved in the Spitzer image, thesupermassiveblack hole surrounded by infalling material is the source of enormous energy drivingtherelativistic jets from the center...

APOD: 2023 April 28 - Runaway Star Alpha Camelopardalis 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. 2023 April 28 Runaway Star Alpha Camelopardalis Image Credit:André Vilhena Explanation: Like a ship plowing through cosmic seas, runaway starAlpha Camelopardalishas produced this graceful arcing bow wave or bow shock.The massive supergiant star moves at over 60kilometers per second through space, compressing theinterstellarmaterial in its path.At the centerof this nearly 6 degree wide view, Alpha Cam is about 25-30 timesas massive as the Sun, 5 times hotter (30,000 kelvins), andover 500,000 times brighter.About 4,000 light-years away in the long-necked constellationCamelopardalis,the star also produces a strong stellar wind.Alpha Cam's bow shock stands off about 10 light-years from the star itself.What set thisstar in motion?Astronomers have long thought that Alpha Cam was flung out ofa nearby cluster of young hot stars due to gravitational interactionswith other cluster members or perhaps by thesupernova explosion of a massive companion star. Tomorrow's picture: ship-borne astronomy <| 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...

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. 2023 April 29 Solar Eclipse from a Ship Image Credit:Fred Espenak Explanation: Along a narrow paththat mostly avoided landfall,the shadow of theNew Moon racedacross planet Earth's southern hemisphereon April 20 to create a rareannular-total orhybrid solar eclipse.From the Indian Ocean off the coast of western Australia,ship-borne eclipse chasers were able to witness 62 secondsof totality thoughwhile anchored near the centerline of the total eclipse track.This ship-borne image of the eclipse capturesthe active Sun's magnificent outer atmosphere orsolar corona streaming into space.A composite of 11 exposures ranging from 1/2000 to 1/2 second,it records an extended range of brightnessto follow details of the corona not quite visible to the eye duringthe total eclipse phase.Of courseeclipsestend to come in pairs.On May 5, thenext Full Moonwill just miss the dark inner part of Earth's shadowin a penumbral lunar eclipse. Total Solar Eclipse of 2023 April Gallery: Notable Submissions to APOD Tomorrow's picture: subtle Saturnian moon <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA...

APOD: 2023 April 27 - The Tarantula Nebula from SuperBIT 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. 2023 April 27 The Tarantula Nebula from SuperBIT Image Credit:SuperBIT,NASA Explanation: TheTarantula Nebula, also known as 30 Doradus,is more than a thousand light-years in diameter,a giant star forming region within nearby satellite galaxy theLarge Magellanic Cloud.About 160 thousand light-years away, it's the largest,most violent star forming region known in the whole LocalGroup of galaxies.The cosmic arachnid is near the center of this spectacular imagetaken during theflight of SuperBIT(Super Pressure Balloon Imaging Telescope),NASA's balloon-borne 0.5 meter telescopenow floating near the edge of space.Within the well-studied Tarantula (NGC 2070),intense radiation,stellar winds and supernova shocks from the central young cluster ofmassive stars, cataloged as R136,energize the nebular glow and shape the spidery filaments.Around the Tarantulaare other star forming regions withyoung star clusters, filaments, and blown-outbubble-shaped clouds.SuperBIT's wide field of view spans over 2 degreesor 4 full moons in the southernconstellation Dorado. Tomorrow's picture: alpha camel leopard <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific...

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. 2023 April 28 Runaway Star Alpha Camelopardalis Image Credit:André Vilhena Explanation: Like a ship plowing through cosmic seas, runaway starAlpha Camelopardalishas produced this graceful arcing bow wave or bow shock.The massive supergiant star moves at over 60kilometers per second through space, compressing theinterstellarmaterial in its path.At the centerof this nearly 6 degree wide view, Alpha Cam is about 25-30 timesas massive as the Sun, 5 times hotter (30,000 kelvins), andover 500,000 times brighter.About 4,000 light-years away in the long-necked constellationCamelopardalis,the star also produces a strong stellar wind.Alpha Cam's bow shock stands off about 10 light-years from the star itself.What set thisstar in motion?Astronomers have long thought that Alpha Cam was flung out ofa nearby cluster of young hot stars due to gravitational interactionswith other cluster members or perhaps by thesupernova explosion of a massive companion star. 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...

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. 2023 April 27 The Tarantula Nebula from SuperBIT Image Credit:SuperBIT,NASA Explanation: TheTarantula Nebula, also known as 30 Doradus,is more than a thousand light-years in diameter,a giant star forming region within nearby satellite galaxy theLarge Magellanic Cloud.About 160 thousand light-years away, it's the largest,most violent star forming region known in the whole LocalGroup of galaxies.The cosmic arachnid is near the center of this spectacular imagetaken during theflight of SuperBIT(Super Pressure Balloon Imaging Telescope),NASA's balloon-borne 0.5 meter telescopenow floating near the edge of space.Within the well-studied Tarantula (NGC 2070),intense radiation,stellar winds and supernova shocks from the central young cluster ofmassive stars, cataloged as R136,energize the nebular glow and shape the spidery filaments.Around the Tarantulaare other star forming regions withyoung star clusters, filaments, and blown-outbubble-shaped clouds.SuperBIT's wide field of view spans over 2 degreesor 4 full moons in the southernconstellation Dorado. Tomorrow's picture: alpha camel leopard <| 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...

APOD: 2023 April 21 - Solar Eclipse from Western Australia 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. 2023 April 21 Solar Eclipse from Western Australia Image Credit &Copyright:Gwenaël Blanck Explanation: Along a narrow paththat mostly avoided landfall,the shadow of the New Moon raced across planet Earth'ssouthern hemisphereon April 20 to create a rareannular-total orhybrid solar eclipse.A mere 62 seconds of totality could be seen though,when the dark central lunar shadow just grazed theNorth West Cape, a peninsula in western Australia.From top to bottom these panels capture the beginning, middle, andend of that fleetingtotal eclipse phase.At start and finish, solar prominences and beads of sunlightstream past the lunar limb.At mid-eclipse thecentral frame revealsthe sight onlyeasily visible during totality and mosttreasured by eclipse chasers, themagnificent coronaof the active Sun.Of course eclipsestend to come in pairs.On May 5, the next Full Moonwill just miss the dark inner part of Earth's shadowin a penumbral lunar eclipse. Total Solar Eclipse of 2023 April Gallery: Notable Submissions to APOD Watch: Planet Earth's annualLyrid Meteor Shower Tomorrow's picture: light-weekend <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss|...

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. 2023 April 22 NGC 1333: Stellar Nursery in Perseus Image Credit:Science -NASA,ESA,STScI,Processing - Varun Bajaj (STScI),Joseph DePasquale (STScI),Jennifer Mack (STScI) Explanation: In visible light NGC 1333 is seen as areflection nebula,dominated by bluish hues characteristic of starlight reflected byinterstellar dust.A mere 1,000 light-years distant toward the heroic constellationPerseus,it lies at the edge of a large, star-forming molecular cloud.This Hubble Space Telescopeclose-up frames a region just over 1 light-yearwide at the estimated distance of NGC 1333.It shows details of the dusty regionalong with telltale hints of contrasty red emission fromHerbig-Haroobjects, jets and shocked glowing gasemanating from recently formed stars.In fact, NGC 1333 contains hundreds of stars less thana million years old, most stillhidden from optical telescopesby the pervasive stardust.The chaotic environment may be similar to one in which our own Sunformed over 4.5 billion years ago.Hubble's stunning imageof the stellar nursery was released to celebratethe 33rd anniversary of the space telescope's launch. Watch: Planet Earth's annualLyrid Meteor Shower Tomorrow's picture: cloudy day <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD|...

APOD: 2023 April 20 - The Dark Seahorse in Cepheus 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. 2023 April 20 The Dark Seahorse in Cepheus Image Credit &Copyright:Jeff Herman Explanation: Spanning light-years, thissuggestive shape known as the Seahorse Nebulaappears in silhouette against a rich, luminous background of stars.Seen toward the royal northern constellation of Cepheus,the dusty, obscuring clouds are part of a Milky Waymolecular cloud some 1,200 light-years distant.It is also listed as Barnard 150 (B150), one of 182dark markings of the skycataloged in the early 20th century by astronomerE. E. Barnard.Packs of low mass stars are formingwithin,but their collapsing cores are only visible at longinfrared wavelengths.Still, the colorful stars of Cepheus add to thispretty, galactic skyscape. 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,NASA Science Activation& Michigan Tech. U.

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. 2023 April 21 Solar Eclipse from Western Australia Image Credit &Copyright:Gwenaël Blanck Explanation: Along a narrow paththat mostly avoided landfall,the shadow of the New Moon raced across planet Earth'ssouthern hemisphereon April 20 to create a rareannular-total orhybrid solar eclipse.A mere 62 seconds of totality could be seen though,when the dark central lunar shadow just grazed theNorth West Cape, a peninsula in western Australia.From top to bottom these panels capture the beginning, middle, andend of that fleetingtotal eclipse phase.At start and finish, solar prominences and beads of sunlightstream past the lunar limb.At mid-eclipse thecentral frame revealsthe sight onlyeasily visible during totality and mosttreasured by eclipse chasers, themagnificent coronaof the active Sun.Of course eclipsestend to come in pairs.On May 5, the next Full Moonwill just miss the dark inner part of Earth's shadowin a penumbral lunar eclipse. 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...

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. 2023 April 20 The Dark Seahorse in Cepheus Image Credit &Copyright:Jeff Herman Explanation: Spanning light-years, thissuggestive shape known as the Seahorse Nebulaappears in silhouette against a rich, luminous background of stars.Seen toward the royal northern constellation of Cepheus,the dusty, obscuring clouds are part of a Milky Waymolecular cloud some 1,200 light-years distant.It is also listed as Barnard 150 (B150), one of 182dark markings of the skycataloged in the early 20th century by astronomerE. E. Barnard.Packs of low mass stars are formingwithin,but their collapsing cores are only visible at longinfrared wavelengths.Still, the colorful stars of Cepheus add to thispretty, galactic skyscape. 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,NASA Science Activation& Michigan Tech. U.

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. 2023 April 15 When Z is for Mars Image Credit &Copyright:Tunc Tezel(TWAN) Explanation: A composite of imagescaptured about a week apartfrom mid August 2022 through late March 2023,this series traces theretrograde motion of ruddy-colored Mars.Progressing from lower right to upper leftMars makes aZ-shaped path as it wanderspast the Pleiades and Hyades star clusters,through the constellation Taurus in planet Earth's night sky.Seen about every two years, Mars doesn'tactually reverse the direction of its orbitto trace out the Z-shape though.Instead, the apparent backwards or retrograde motion withrespect to the background stars is areflection of the orbital motion of Earth itself.Retrograde motion can be seen each time Earth overtakesand laps planets orbiting farther from the Sun, theEarth moving more rapidly through its own relatively close-in orbit. High in northern hemisphere skies theRed Planet was opposite the Sunand at its closest and brightest on December 8,near the center of the frame.Seen close to Mars,a popular visitor to the inner Solar System,comet ZTF (C/2022 E3),was also captured on two dates, February 10 and February 16. Tomorrow's picture:...

APOD: 2023 April 14 - Portrait of NGC 3628 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. 2023 April 14 Portrait of NGC 3628 Image Credit &Copyright:Mike Selby &Mark Hanson Explanation: Sharp telescopic views ofNGC 3628show a puffy galactic disk divided by dark dust lanes.Of course,this portraitof the magnificent, edge-on spiral galaxy puts some astronomersin mind of its popular moniker,the Hamburger Galaxy.It also reveals a small galaxy nearby (below), likely a satellite ofNGC 3628, and a very faint but extensivetidal tail.The drawn out tail stretches for about 300,000light-years, even beyond the left edge of the frame.NGC 3628 shares its neighborhood in thelocal universe with two other large spiralsM65 andM66 in a groupingotherwise known as the Leo Triplet.Gravitationalinteractionswith itscosmic neighbors are likely responsible for creating the tidal tail,as well as the extended flare and warp of this spiral's disk.The tantalizingisland universeitself is about 100,000 light-years across and 35 million light-yearsaway in the northern springtime constellation Leo. Tomorrow's picture: Z is for Mars <| Archive| Submissions | Index| Search| Calendar| RSS| Education| About APOD| Discuss| > Authors & editors: Robert Nemiroff(MTU) &Jerry Bonnell (UMCP)NASA Official: Phillip NewmanSpecific...