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Astronomy Picture of the Day (APoD)
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Inside the Coma Cluster of Galaxies
Image Credit: +NASA, +European Space Agency, ESA, Hubble Heritage (STScI/AURA); 
Acknowledgment: D. Carter (LJMU) et al. and the Coma HST ACS Treasury Team

Almost every object in the above photograph is a galaxy. The Coma Cluster of Galaxies pictured above is one of the densest clusters known - it contains thousands of galaxies. Each of these galaxies houses billions of stars - just as our own Milky Way Galaxy does. Although nearby when compared to most other clusters, light from the Coma Cluster still takes hundreds of millions of years to reach us. In fact, the Coma Cluster is so big it takes light millions of years just to go from one side to the other! The above mosaic of images of a small portion of Coma was taken in unprecedented detail in 2006 by the Hubble Space Telescope to investigate how galaxies in rich clusters form and evolve. Most galaxies in Coma and other clusters are ellipticals, although some imaged here are clearly spirals. The spiral galaxy on the upper left of the above image can also be found as one of the bluer galaxies on the upper left of this wider field image. In the background thousands of unrelated galaxies are visible far across the universe.
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Bearing in mind the distances involved it is quite possible some, if not all, of these galaxies no longer exist and are effectively ghosts of long dead habitats. 
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Long Lovejoy and Little Dumbbell
Image Credit & Copyright: Rolando Ligustri (CARA Project, CAST)

Buffeted by the solar wind, Comet Lovejoy's crooked ion tail stretches over 3 degrees across this telescopic field of view, recorded on February 20. The starry background includes awesome bluish star Phi Persei below, and pretty planetary nebula M76 just above Lovejoy's long tail. Also known as the Little Dumbbell Nebula, after its brighter cousin M27 the Dumbbell Nebula, M76 is only a Full Moon's width away from the comet's greenish coma. Still shining in northern hemisphere skies, this Comet Lovejoy (C/2014 Q2) is outbound from the inner solar system some 10 light-minutes or 190 million kilometers from Earth. But the Little Dumbbell actually lies 3 to 5 thousand light-years away. Now sweeping steadily north toward the constellation Cassiopeia Comet Lovejoy is fading more slowly than predicted and is still a good target for small telescopes.
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The Rosette Nebula in Hydrogen and Oxygen
Image Credit & Copyright: Arno Rottal (Far-Light-Photography)

The Rosette Nebula is not the only cosmic cloud of gas and dust to evoke the imagery of flowers -- but it is the most famous. At the edge of a large molecular cloud in Monoceros, some 5,000 light years away, the petals of this rose are actually a stellar nursery whose lovely, symmetric shape is sculpted by the winds and radiation from its central cluster of hot young stars. The stars in the energetic cluster, cataloged as NGC 2244, are only a few million years old, while the central cavity in the Rosette Nebula, cataloged as NGC 2237, is about 50 light-years in diameter. The nebula can be seen firsthand with a small telescope toward the constellation of the Unicorn (Monoceros).
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Dusty me  likey.
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The Milky Way Over the Arizona Toadstools
Image Credit & Copyright: David Lane & R. Gendler (3 insets)

Which is older -- the rocks you see on the ground or the light you see from the sky? Usually it’s the rocks that are older, with their origin sentiments deposited well before light left any of the stars or nebulas you see in the sky. However, if you can see, through a telescope, a distant galaxy far across the universe -- further than Andromeda or spiral galaxy NGC 7331 (inset) -- then you are seeing light even more ancient. Featured here, the central disk of our Milky Way Galaxy arches over Toadstool hoodoos rock formations in northern Arizona, USA. The unusual Toadstool rock caps are relatively hard sandstone that wind has eroded more slowly than the softer sandstone underneath. The green bands are airglow, light emitted by the stimulated air in Earth's atmosphere. On the lower right is a time-lapse camera set up to capture the sky rotating behind the picturesque foreground scene.
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super epic
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45 Days in the Sun
Image Credit & Copyright: Csaba Kovács

From January 11 to February 25 2013, a pinhole camera sat in a field near Budapest, Hungary, planet Earth to create this intriguing solargraph. And for 45 days, an old Antonov An-2 biplane stood still while the Sun rose and set. The camera's continuous exposure began about 20 days after the northern hemispere's winter solstice, so each day the Sun's trail arcs steadily higher through the sky. These days in the Sun were recorded on a piece of black and white photosensitive paper tucked in to the simple plastic film container. The long exposure produced a visible color image on the paper that was then digitally scanned. Of course, cloudy days left gaps in the solargraph's Sun trails.
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What are the light colored bands above the airplane?
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Palomar 12
Image Credit: +European Space Agency, ESA/Hubble, +NASA

Palomar 12 was not born here. The stars of the globular cluster, first identified in the Palomar Sky Survey, are younger than those in other globular star clusters that roam the halo of our Milky Way Galaxy. Palomar 12's position in our galaxy and measured motion suggest its home was once the Sagittarius Dwarf Elliptical Galaxy, a small satellite of the Milky Way. Disrupted by gravitational tides during close encounters the satellite galaxy has lost its stars to the larger Milky Way. Now part of the Milky Way's halo, the tidal capture of Palomar 12 likely took place some 1.7 billion years ago. Seen behind spiky foreground stars in the sharp Hubble image, Palomar 12 spans nearly 60 light-years. It lies about 60,000 light-years away, toward the constellation Capricornus.
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Have them in circles
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Moon-Venus-Mars Skyline
Image Credit & Copyright: Jay Ouellet

Taken on February 20, five different exposures made in rapid succession were used to created this tantalizing telephoto image. In combination, they reveal a wide range of brightness visible to the eye on that frigid evening, from the urban glow of the Quebec City skyline to the triple conjunction of Moon, Venus and Mars. Shortly after sunset the young Moon shows off its bright crescent next to brilliant Venus. Fainter Mars is near the top of the frame. Though details in the Moon's sunlit crescent are washed out, features on the dark, shadowed part of the lunar disk are remarkably clear. Still lacking city lights the lunar night is illuminated solely by earthshine, light reflected from the sunlit side of planet Earth.
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Love it 
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Love and War by Moonlight
Image Credit & Copyright: Kevin Bourque

Venus, named for the Roman goddess of love, and Mars, the war god's namesake, came together by moonlight in this lovely skyview, recorded on February 20 from Charleston, South Carolina, USA, planet Earth. Made in twilight with a digital camera, the three second time exposure also records earthshine illuminating the otherwise dark surface of the young crescent Moon. Of course, the Moon has moved on from this much anticipated triple conjunction. Venus still shines in the west though as the evening star, third brightest object in Earth's sky, after the Sun and the Moon itself. Seen here within almost a Moon's width of Venus, much fainter Mars approached even closer on the following evening. But Mars has since been moving slowly away from brilliant Venus, though Mars is still visible too in the western twilight.
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Lovely sight.
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Unusual Plumes Above Mars
Image Credit & Copyright: W. Jaeschke

What is creating unusual plumes on Mars? No one is sure. Noted and confirmed by a global contingent of amateur astronomers on photos of the red planet in March 2012, possibly similar plumes have now been found on archived images as far back as 1997. Since the plumes reach 200 kilometers up, they seem too high to be related to wind-blown surface dust. Since one plume lasted for eleven days, it seemed too long lasting to be related to aurora. Amateur astronomers will surely continue to monitor the terminator and edge regions of Mars for new high plumes, and the armada of satellites orbiting Mars may be called upon to verify and study any newly reported plume that become visible. The featured 35-minute time-lapse animation was taken on 2012 March 20 by the plume's discoverer -- an attorney from Pennsylvania, USA.
Olympus Zeus's profile photoToday's Memory's profile photoReginald Gordon's profile photoAlee Al-Lihabi's profile photo
Dear Mr. Gerba, you're not your, and they're not there. Clarity is so important 
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The Dark River to Antares
Credit & Copyright: Jason Jennings

Connecting the Pipe Nebula to the colorful region near bright star Antares is a dark cloud dubbed the Dark River, flowing from the picture's left edge. Murky looking, the Dark River's appearance is caused by dust obscuring background starlight, although the dark nebula contains mostly hydrogen and molecular gas. Surrounded by dust, Antares, a red supergiant star, creates an unusual bright yellowish reflection nebula. Above it, bright blue double star Rho Ophiuchi is embedded in one of the more typical bluish reflection nebulae, while red emission nebulae are also scattered around the region. Globular star cluster M4 is just seen above and right of Antares, though it lies far behind the colorful clouds, at a distance of some 7,000 light-years. The Dark River itself is about 500 light years away. The colorful skyscape is a mosaic of telescopic images spanning nearly 10 degrees (20 Full Moons) across the sky in the constellation of the Scorpion (Scorpius).
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An Evening Sky Conjunction
Image Credit & Copyright: Tunç Tezel (TWAN)

Eight years ago, an evening sky held this lovely pairing of a young crescent Moon and brilliant Venus. Seen near the western horizon, the close conjunction and its wintry reflection were captured from Bolu, Turkey, planet Earth on February 19, 2007. In the 8 Earth years since this photograph was taken Venus has orbited the Sun almost exactly 13 times, so the Sun and Venus have now returned to the same the configuration in Earth's sky. And since every 8 years the Moon also nearly repeats its phases for a given time of year, a very similar crescent Moon-Venus conjunction will again appear in planet Earth's evening skies tonight. But the February 20, 2015 version of the conjunction will also include planet Mars. Much fainter Mars will wander even closer to Venus by the evening of February 21.
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MOODY and ROMANTIC..... oh my oh my
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Dark Craters and Bright Spots Revealed on Asteroid Ceres
Image Credit: +NASA, +NASA Jet Propulsion Laboratory - Caltech, UCLA, MPS/DLR/IDA

What are those bright spots on asteroid Ceres? As the robotic spacecraft Dawn approaches the largest asteroid in the asteroid belt, the puzzle only deepens. Sharper new images taken last week and released yesterday indicate, as expected, that most of the surface of dwarf planet Ceres is dark and heavily cratered like our Moon and the planet Mercury. The new images do not clearly indicate, however, the nature of comparatively bright spots -- although more of them are seen to exist. The enigmatic spots were first noticed on Texas-sized Ceres a few weeks ago during Dawn's approach. The intriguing mystery might well be solved quickly as Dawn continues to advance toward Ceres, being on schedule to enter orbit on March 6.
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They keep making the same mistake too.
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