Astronomy Picture of the Day (General/Chat)

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  • Astronomy Picture of the Day -- The Wolf's Moon

    01/20/2012 3:39:49 AM PST · by SunkenCiv · 9 replies · 1+ views
    NASA ^ | January 20, 2012 | (see photo credit)
    Explanation: A Full Moon rising can be a dramatic celestial sight, and Full Moons can have many names. Captured on January 8 from Ötersund, Sweden, this evocative moonrise portrait might make you feel the cold of winter in the north. If you can also imagine wolves howling in the distance then you probably understand why Native Americans would have called it the Wolf Moon, their traditional name for the first Full Moon in January. The photographer reports that no wolves were heard though, as he watched this beautiful Full Moon rise in fading light over the eastern horizon, echoing the...
  • Astronomy Picture of the Day -- The Hunter's Stars

    01/19/2012 5:16:02 PM PST · by SunkenCiv · 17 replies
    NASA ^ | January 19, 2012 | (see photo credit)
    Explanation: Begirt with many a blazing star, Orion, the Hunter, is one of the most easily recognizable constellations. In this night skyscape from January 15, the hunter's stars rise in the northern hemisphere's winter sky, framed by bare trees and bounded below by terrestrial lights around Lough Eske (Lake of Fish) in County Donegal, Ireland. Red giant star Betelgeuse is striking in yellowish hues at Orion's shoulder above and left of center. Rivaling the bright red giant, Rigel, a blue supergiant star holds the opposing position near Orion's foot. Of course, the sword of Orion hangs from the hunter's three...
  • Astronomy Picture of the Day -- Cygnus-X: The Inner Workings of a Nearby Star Factory

    01/18/2012 4:19:10 AM PST · by SunkenCiv · 10 replies
    NASA ^ | January 18, 2012 | (see photo credit)
    Explanation: How do stars form? To help study this complex issue, astronomers took a deep infrared image of Cygnus X, the largest known star forming region in the entire Milky Way Galaxy. The above recently-released image was taken in 2009 by the orbiting Spitzer Space Telescope and digitally translated into colors humans can see, with the hottest regions colored the most blue. Visible are large bubbles of hot gas inflated by the winds of massive stars soon after they form. Current models posit that these expanding bubbles sweep up gas and sometimes even collide, frequently creating regions dense enough to...
  • Astronomy Picture of the Day -- IC 2118: The Witch Head Nebula

    01/16/2012 9:18:55 PM PST · by SunkenCiv · 37 replies
    NASA ^ | January 17, 2012 | (see photo credit)
    Explanation: Double, double toil and trouble; Fire burn, and cauldron bubble -- maybe Macbeth should have consulted the Witch Head Nebula. This suggestively shaped reflection nebula is associated with the bright star Rigel in the constellation Orion. More formally known as IC 2118, the Witch Head Nebula glows primarily by light reflected from bright star Rigel, located just below the lower edge of the above image. Fine dust in the nebula reflects the light. The blue color is caused not only by Rigel's blue color but because the dust grains reflect blue light more efficiently than red. The same physical...
  • Astronomy Picture of the Day -- Zodiacal Light and the False Dawn

    01/16/2012 10:37:38 AM PST · by SunkenCiv · 9 replies
    NASA ^ | January 16, 2012 | (see photo credit)
    Explanation: Is it dawn or false dawn? During certain times of the year, the horizon near the rising Sun will begin to glow unusually early. This early glow does not originate directly from the Sun, but rather from sunlight reflected by interplanetary dust. Called zodiacal light, the glowing triangle of light may be mistaken, for a while, for a sunrise, and so may be called a false dawn. Pictured above, two false dawns were recorded in time lapse movies each spanning about five hours from the perch of the highest observatory in the world: Mount Saraswati near Hanle, India. At...
  • Astronomy Picture of the Day -- Infrared Portrait of the Large Magellanic Cloud

    01/15/2012 3:50:08 PM PST · by SunkenCiv · 16 replies
    NASA ^ | January 15, 2012 | (see photo credit)
    Explanation: Cosmic dust clouds ripple across this infrared portrait of our Milky Way's satellite galaxy, the Large Magellanic Cloud. In fact, the remarkable composite image from the Herschel Space Observatory and the Spitzer Space Telescope show that dust clouds fill this neighboring dwarf galaxy, much like dust along the plane of the Milky Way itself. The dust temperatures tend to trace star forming activity. Spitzer data in blue hues indicate warm dust heated by young stars. Herschel's instruments contributed the image data shown in red and green, revealing dust emission from cooler and intermediate regions where star formation is just...
  • Astronomy Picture of the Day -- NGC 6369: The Little Ghost Nebula

    01/13/2012 9:23:04 PM PST · by SunkenCiv · 6 replies · 1+ views
    NASA ^ | January 14, 2012 | (see photo credit)
    Explanation: This pretty planetary nebula, cataloged as NGC 6369, was discovered by 18th century astronomer William Herschel as he used a telescope to explore the medicinal constellation Ophiucus. Round and planet-shaped, the nebula is also relatively faint and has acquired the popular moniker of Little Ghost Nebula. Planetary nebulae in general are not at all related to planets, but instead are created at the end of a sun-like star's life as its outer layers expand into space while the star's core shrinks to become a white dwarf. The transformed white dwarf star, seen near the center, radiates strongly at ultraviolet...
  • Astronomy Picture of the Day -- Saturn's Iapetus: Painted Moon

    01/13/2012 5:55:13 PM PST · by SunkenCiv · 18 replies · 1+ views
    NASA ^ | January 13, 2012 | (see photo credit)
    Explanation: What has happened to Saturn's moon Iapetus? Vast sections of this strange world are dark as coal, while others are as bright as ice. The composition of the dark material is unknown, but infrared spectra indicate that it possibly contains some dark form of carbon. Iapetus also has an unusual equatorial ridge that makes it appear like a walnut. To help better understand this seemingly painted moon, NASA directed the robotic Cassini spacecraft orbiting Saturn to swoop within 2,000 kilometers in 2007. Pictured above, from about 75,000 kilometers out, Cassini's trajectory allowed unprecedented imaging of the hemisphere of Iapetus...
  • Astronomy Picture of the Day -- The Case of the Missing Supernova Companion

    01/11/2012 9:39:24 PM PST · by SunkenCiv · 9 replies
    NASA ^ | January 12, 2012 | (see photo credit)
    Explanation: Where's the other star? At the center of this supernova remnant should be the companion star to the star that blew up. Identifying this star is important for understanding just how Type Ia supernova detonate, which in turn could lead to a better understanding of why the brightness of such explosions are so predictable, which in turn is key to calibrating the entire nature of our universe. The trouble is that even a careful inspection of the center of SNR 0509-67.5 has not found any star at all. This indicates that the companion is intrinsically very faint -- much...
  • Astronomy Picture of the Day -- Little Planet Lovejoy

    01/10/2012 9:47:55 PM PST · by SunkenCiv · 5 replies · 1+ views
    NASA ^ | January 11, 2012 | (see photo credit)
    Explanation: Once a bright apparition in the southern hemisphere dawn Comet Lovejoy is fading, but its long tail still stretches across skies near the south celestial pole. Captured on the morning of December 30th, the comet appears near edge of this little planet as well. Of course, the little planet is actually planet Earth and the image was created from a 12 frame mosaic used to construct a spherical panorama. The type of stereographic projection used to map the image pixels is centered directly below the camera and is known as the little planet projection. Stars surrounding this little planet...
  • Astronomy Picture of the Day -- Vesta Rocks

    01/10/2012 6:13:14 PM PST · by SunkenCiv · 11 replies · 1+ views
    NASA ^ | December 10, 2011 | (see photo credit)
    Explanation: These colorful images are of thin slices of meteorites viewed through a polarizing microscope. Part of the group classified as HED (Howardite, Eucrite, Diogenite) meteorites for their mineral content, they likely fell to Earth from 4 Vesta, the mainbelt asteroid currently being explored by NASA's Dawn spacecraft. Why are they thought to be from Vesta? Because the HED meteorites have visible and infrared spectra that match the spectrum of that small world. The hypothesis of their origin on Vesta is also consistent with data from Dawn's ongoing observations. Excavated by impacts, the diogenites shown here would have originated deep...
  • Astronomy Picture of the Day -- Bright Star Regulus near the Leo I Dwarf Galaxy

    01/09/2012 9:23:36 PM PST · by SunkenCiv · 9 replies · 1+ views
    NASA ^ | January 09, 2012 | (see photo credit)
    Explanation: The star near the top is so bright that it is sometimes hard to notice the galaxy toward the bottom. Pictured above, both the star, Regulus, and the galaxy, Leo I, can be found within one degree of each other toward the constellation of the Lion (Leo). Regulus is part of a multiple star system, with a close companion double star visible to the lower left of the young main sequence star. Leo I is a dwarf spheroidal galaxy in the Local Group of galaxies dominated by our Milky Way Galaxy and M31. Leo I is thought to be...
  • Astronomy Picture of the Day -- Facing NGC 6946

    01/09/2012 7:01:52 PM PST · by SunkenCiv · 13 replies · 1+ views
    NASA ^ | January 09, 2012 | (see photo credit)
    Explanation: From our vantage point in the Milky Way Galaxy, we see NGC 6946 face-on. The big, beautiful spiral galaxy is located just 10 million light-years away, behind a veil of foreground dust and stars in the high and far-off constellation of Cepheus. From the core outward, the galaxy's colors change from the yellowish light of old stars in the center to young blue star clusters and reddish star forming regions along the loose, fragmented spiral arms. NGC 6946 is also bright in infrared light and rich in gas and dust, exhibiting a high star birth and death rate. In...
  • Astronomy Picture of the Day -- Lighthouse and Meteor

    01/08/2012 5:56:01 PM PST · by SunkenCiv · 7 replies
    NASA ^ | January 08, 2012 | (see photo credit)
    Explanation: Named for a forgotten constellation, the Quadrantid Meteor Shower is an annual event for planet Earth's northern hemisphere skygazers. It usually peaks briefly in the cold, early morning hours of January 4. The shower's radiant point on the sky lies within the old, astronomically obsolete constellation Quadrans Muralis. That position is situated near the boundaries of the modern constellations Hercules, Bootes, and Draco. Many of this year's Quadrantid meteors were dim, but the one captured in this north-looking view is bright and easy to spot. In the foreground is the Maurice River's East Point Lighthouse located near the southern...
  • Astronomy Picture of the Day -- Grand Spiral Galaxy NGC 1232

    01/07/2012 2:17:12 PM PST · by SunkenCiv · 18 replies · 1+ views
    NASA ^ | January 07, 2012 | (see photo credit)
    Explanation: Galaxies are fascinating not only for what is visible, but for what is invisible. Grand spiral galaxy NGC 1232, captured in detail by one of the new Very Large Telescopes, is a good example. The visible is dominated by millions of bright stars and dark dust, caught up in a gravitational swirl of spiral arms revolving about the center. Open clusters containing bright blue stars can be seen sprinkled along these spiral arms, while dark lanes of dense interstellar dust can be seen sprinkled between them. Less visible, but detectable, are billions of dim normal stars and vast tracts...
  • Astronomy Picture of the Day -- A Wide Field Image of the Galactic Center

    01/06/2012 2:27:26 PM PST · by SunkenCiv · 15 replies
    NASA ^ | January 06, 2012 | (see photo credit)
    Explanation: From Sagittarius to Scorpius, the central Milky Way is a truly beautiful part of planet Earth's night sky. The gorgeous region is captured in this wide field image spanning about 30 degrees. The impressive cosmic vista, taken in 2010, shows off intricate dust lanes, bright nebulae, and star clusters scattered through our galaxy's rich central starfields. Starting on the left, look for the Lagoon and Trifid nebulae, the Cat's Paw, while on the right lies the Pipe dark nebula, and the colorful clouds of Rho Ophiuchi and Antares (right). The actual center of our Galaxy lies about 26,000 light...
  • Astronomy Picture of the Day -- Ringside with Titan and Dione

    01/05/2012 6:45:53 PM PST · by SunkenCiv · 20 replies
    NASA ^ | January 05, 2012 | (see photo credit)
    Explanation: Orbiting in the plane of Saturn's rings, Saturnian moons have a perpetual ringside view of the gorgeous gas giant planet. Of course, while passing near the ring plane the Cassini spacecraft also shares their stunning perspective. The rings themselves can be seen slicing across the middle of this Cassini snapshot from May of last year. The scene features Titan, largest, and Dione, third largest moon of Saturn. Remarkably thin, the bright rings still cast arcing shadows across the planet's cloud tops at the bottom of the frame. Pale Dione is about 1,100 kilometers across and orbits over 300,000 kilometers...
  • Astronomy Picture of the Day -- Starburst Galaxy IC 10

    01/04/2012 7:09:59 PM PST · by SunkenCiv · 30 replies
    NASA ^ | January 04, 2012 | (see photo credit)
    Explanation: Lurking behind dust and stars near the plane of our Milky Way Galaxy, IC 10 is a mere 2.3 million light-years distant. Even though its light is dimmed by intervening dust, the irregular dwarf galaxy still shows off vigorous star-forming regions that shine with a telltale reddish glow in this colorful skyscape. In fact, also a member of the Local Group of galaxies, IC 10 is the closest known starburst galaxy. Compared to other Local Group galaxies, IC 10 has a large population of newly formed stars that are massive and intrinsically very bright, including a luminous X-ray binary...
  • Astronomy Picture of the Day -- A Full Sky Aurora Over Norway

    01/02/2012 9:40:39 PM PST · by SunkenCiv · 24 replies
    NASA ^ | January 03, 2012 | (see photo credit)
    Explanation: Higher than the highest building, higher than the highest mountain, higher than the highest airplane, lies the realm of the aurora. Auroras rarely reach below 60 kilometers, and can range up to 1000 kilometers. Aurora light results from energetic electrons and protons striking molecules in the Earth's atmosphere. Frequently, when viewed from space, a complete aurora will appear as a circle around one of the Earth's magnetic poles. The above wide angle image, horizontally compressed, captured an unexpected auroral display that stretched across the sky one month ago over eastern Norway.
  • Astronomy Picture of the Day -- Spot the Moon

    01/01/2012 10:04:11 PM PST · by SunkenCiv · 14 replies
    NASA ^ | January 02, 2012 | (see photo credit)
    Explanation: Where's the full Moon? Somewhere in this image, the Earth's Moon is hiding. The entire Moon is visible, in its completely full phase, in plain sight. Even the photographer's keen eye couldn't find it even though he knew exactly where to look -- only the long exposure of his camera picked it up -- barely. Although by now you might be congratulating yourself on finding it, why was it so difficult to see? For one reason, this photograph was taken during the total lunar eclipse last month, when the Earth's shadow made the Moon much dimmer than a normal...
  • Astronomy Picture of the Day -- To Fly Free in Space

    01/01/2012 9:59:44 PM PST · by SunkenCiv · 13 replies
    NASA ^ | January 01, 2012 | (see photo credit)
    Explanation: At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured above, was floating free in space. McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "untethered space walk"during Space Shuttle mission 41-B in 1984. The MMU works by shooting jets of nitrogen and has since been used to help deploy and retrieve satellites. With a mass over 140 kilograms, an MMU is heavy on Earth, but, like everything, is...
  • Astronomy Picture of the Day -- Comet Lovejoy and the ISS

    12/30/2011 9:36:05 PM PST · by SunkenCiv · 7 replies
    NASA ^ | December 31, 2011 | (see photo credit)
    Explanation: On December 24, Comet Lovejoy rose in dawn's twilight, arcing above the eastern horizon, its tails swept back by the solar wind and sunlight. Seen on the left is the comet's early morning appearance alongside the southern Milky Way from the town of Intendente Alvear, La Pampa province, Argentina. The short star trails include bright southern sky stars Alpha and Beta Centauri near the center of the frame, but the long bright streak that crosses the comet tails is a little closer to home. Waiting for the proper moment to start his exposure, the photographer has also caught the...
  • Astronomy Picture of the Day -- The Diner at the Center of the Galaxy

    12/29/2011 9:54:25 PM PST · by SunkenCiv · 20 replies
    NASA ^ | December 30, 2011 | (see photo credit)
    Explanation: The monster at the center of our Galaxy is about to get fed. Recent observations by the Very Large Telescopes indicate that a cloud of gas will venture too close to the supermassive black hole at the Galactic center. The gas cloud is being disrupted, stretched out, heated up, and some of it is expected to fall into the black hole over the next two years. In this artist's illustration, what remains of the blob after a close pass to the black hole is shown in red and yellow, arching out from the gravitational death trap to its right....
  • Astronomy Picture of the Day -- Conjunction at Sunset

    12/28/2011 9:27:51 PM PST · by SunkenCiv · 6 replies
    NASA ^ | December 29, 2011 | (see photo credit)
    Explanation: While Comet Lovejoy entertained early morning risers in in the southern hemisphere, a lovely conjunction of a young crescent Moon and Venus graced western skies at sunset. Captured on December 26th the conjunction, with beautiful sunset colors above and below, is seen here over Viverone Lake near Turin, Italy. But if you've been outdoors at all lately enjoying sunsets on planet Earth, then you've probably noticed Venus low in the west as the season's brilliant evening star. Sometimes mistaken for a terrestrial light near the horizon, Venus is the third brightest celestial beacon, after the Sun and Moon. That...
  • Astronomy Picture of the Day -- Comet Lovejoy over Paranal

    12/28/2011 2:28:24 PM PST · by SunkenCiv · 10 replies
    NASA ^ | December 28, 2011 | (see photo credit)
    Explanation: Comet Lovejoy (C/2011 W3) survived its close encounter with the Sun earlier this month, taking its place among wonders of the southern skies just in time for Christmas. Seen here before sunrise from Paranal Observatory in Chile, the sungrazing comet's tails stretch far above the eastern horizon. Spanning over 20 degrees they rise alongside the plane of the our Milky Way galaxy. A breathtaking spectacle in itself, Lovejoy performs on this celestial stage with southern stars and nebulae, including the Large and Small Magellanic clouds right of the telescope dome, and the glow of zodiacal light along the left...
  • Astronomy Picture of the Day -- M27: The Dumbbell Nebula

    12/27/2011 4:12:14 AM PST · by SunkenCiv · 5 replies
    NASA ^ | December 27, 2011 | (see photo credit)
    Explanation: The first hint of what will become of our Sun was discovered inadvertently in 1764. At that time, Charles Messier was compiling a list of diffuse objects not to be confused with comets. The 27th object on Messier's list, now known as M27 or the Dumbbell Nebula, is a planetary nebula, the type of nebula our Sun will produce when nuclear fusion stops in its core. M27 is one of the brightest planetary nebulae on the sky, and can be seen toward the constellation of the Fox (Vulpecula) with binoculars. It takes light about 1000 years to reach us...
  • Astronomy Picture of the Day -- Pelican Nebula Close-up

    12/26/2011 6:22:05 PM PST · by SunkenCiv · 15 replies
    NASA ^ | November 26, 2011 | (see photo credit)
    Explanation: The prominent ridge of emission featured in this vivid skyscape is designated IC 5067. Part of a larger emission nebula with a distinctive shape, popularly called The Pelican Nebula, the ridge spans about 10 light-years and follows the curve of the cosmic pelican's head and neck. The Pelican Nebula close-up was constructed from narrowband data mapping emission from sulfur, hydrogen, and oxygen atoms to red, green, and blue colors. Fantastic, dark shapes inhabiting the view are clouds of cool gas and dust sculpted by energetic radiation from young, hot, massive stars. But stars are also forming within the dark...
  • Astronomy Picture of the Day -- M1: The Crab Nebula from Hubble

    12/25/2011 4:22:54 PM PST · by SunkenCiv · 54 replies
    NASA ^ | December 25, 2011 | (see photo credit)
    Explanation: This is the mess that is left when a star explodes. The Crab Nebula, the result of a supernova seen in 1054 AD, is filled with mysterious filaments. The filaments are not only tremendously complex, but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The above image, taken by the Hubble Space Telescope, is presented in three colors chosen for scientific interest. The Crab Nebula spans about 10 light-years. In the nebula's very center lies a pulsar: a neutron star as massive as the Sun but...
  • Astronomy Picture of the Day -- Eclipsed Moon in the Morning

    12/24/2011 8:08:50 AM PST · by SunkenCiv · 18 replies
    NASA ^ | December 24, 2011 | (see photo credit)
    Explanation: December's lunar eclipse graced early morning skies over the Rocky Mountains in Colorado, USA. There, this wintry scene finds the Moon in a cold blue twilight sky near the western horizon, above the snowy North American Continental Divide. About 22 minutes before the sunrise, the reddened lunar disk is almost completely immersed in Earth's dark shadow. This dramatic Rocky Mountain moon set during the eclipse total phase. But all parts of the geocentric celestial event were seen from Pacific regions, Asia, and Australia, including the entire 51 minutes of totality, and parts of the final eclipse of 2011 were...
  • Astronomy Picture of the Day -- Shell Galaxy NGC 7600

    12/23/2011 3:15:42 AM PST · by SunkenCiv · 11 replies
    NASA ^ | December 23, 2011 | (see photo credit)
    Explanation: Similar in size to the Milky Way, elliptical galaxy NGC 7600 is about 150 thousand light-years distant. In this deep image, spanning about 1/2 degree on the sky toward the constellation Aquarius, NGC 7600 sports a remarkable outer halo of nested shells and broad circumgalactic structures. The tantalizing features can be explained by the accretion of dark matter and stars on a cosmic timescale. In fact, a movie generated by simulating galaxy formation using a cosmological model with cold dark matter for the halos of merging galaxies reproduces the appearance of NGC 7600 in amazing detail. The remarkable simulation...
  • Astronomy Picture of the Day -- Through a Sun Tunnel

    12/22/2011 7:55:27 AM PST · by SunkenCiv · 12 replies
    NASA ^ | December 22, 2011 | (see photo credit)
    Explanation: Today the Sun stands still at 05:30 UT. Halting its steady march toward southern declinations and begining its annual journey north, the event is known as a solstice. In the northern hemisphere December's solstice marks the astronomical start of winter. And if you're in the Great Basin Desert outside of Lucin, Utah, USA, near solstice dates you can watch the Sun rise and set through Sun Tunnels. A monumental earthwork by artist Nancy Holt, the Sun Tunnels are constructed of four 9 foot diameter cast concrete pipes each 18 feet long. The tunnels are arranged in a wide X...
  • Astronomy Picture of the Day -- A Horseshoe Einstein Ring from Hubble

    12/22/2011 7:55:08 AM PST · by SunkenCiv · 18 replies
    NASA ^ | December 21, 2011 | (see photo credit)
    Explanation: What's large and blue and can wrap itself around an entire galaxy? A gravitational lens mirage. Pictured above, the gravity of a luminous red galaxy (LRG) has gravitationally distorted the light from a much more distant blue galaxy. More typically, such light bending results in two discernible images of the distant galaxy, but here the lens alignment is so precise that the background galaxy is distorted into a horseshoe -- a nearly complete ring. Since such a lensing effect was generally predicted in some detail by Albert Einstein over 70 years ago, rings like this are now known as...
  • Astronomy Picture of the Day -- NGC 253: The Sculptor Galaxy

    12/20/2011 2:31:02 AM PST · by SunkenCiv · 26 replies · 1+ views
    NASA ^ | December 20, 2011 | (see photo credit)
    Explanation: NGC 253 is not only one of the brightest spiral galaxies visible, it is also one of the dustiest. Discovered in 1783 by Caroline Herschel in the constellation of Sculptor, NGC 253 lies only about ten million light-years distant. NGC 253 is the largest member of the Sculptor Group of Galaxies, the nearest group to our own Local Group of Galaxies. The dense dark dust accompanies a high star formation rate, giving NGC 253 the designation of starburst galaxy. Visible in the above photograph is the active central nucleus, also known to be a bright source of X-rays and...
  • Astronomy Picture of the Day -- A Geminid Meteor Over Iran

    12/19/2011 8:55:40 AM PST · by SunkenCiv · 9 replies
    NASA ^ | December 19, 2011 | (see photo credit)
    Explanation: Some beautiful things begin as grains of sand. Locked in an oyster, a granule grows into an iridescent pearl, lustrous and lovely to behold. While hurtling through the atmosphere at 35 kilometers per second, a generous cosmic sand grain becomes an awe-inspiring meteor, its transient beauty displayed for any who care to watch. This years Geminid meteor shower peaked last week with sky enthusiasts counting as many as 150 meteors per hour, despite the din of bright moon. Pictured above the Taftan volcano in southeast Iran, a meteor streaks between the bright star Sirius on the far left and...
  • Astronomy Picture of the Day -- Hints of Higgs from the Large Hadron Collider

    12/18/2011 8:13:12 AM PST · by SunkenCiv · 32 replies
    NASA ^ | December 18, 2011 | (see photo credit)
    Explanation: Why do objects have mass? To help find out, Europe's CERN has built the Large Hadron Collider (LHC), the most powerful particle accelerator yet created by humans. Since 2008, the LHC smashed protons into each other with unprecedented impact speeds. The LHC is exploring the leading explanation that mass arises from ordinary particles slogging through an otherwise invisible but pervasive field of virtual Higgs particles. Were high energy colliding particles to create real Higgs bosons, the Higgs mechanism for mass creation will be bolstered. Last week, two LHC groups reported on preliminary indications that the Higgs boson might exist...
  • Astronomy Picture of the Day -- Comet Lovejoy: Sungrazing Survivor

    12/16/2011 9:18:57 PM PST · by SunkenCiv · 13 replies
    NASA ^ | December 17, 2011 | (see photo credit)
    Explanation: Like most other sungrazing comets, Comet Lovejoy (C/2011 W3) was not expected to survive its close encounter with the Sun. But it did. This image from a coronograph onboard the sun-staring SOHO spacecraft identifies the still inbound remnants of the tail, with the brilliant head or coma emerging from the solar glare on December 16. The Sun's position, behind an occulting disk to block the overwhelming glare, is indicated by the white circle. Separated from its tail, Comet Lovejoy's coma is so bright it saturates the camera's pixels creating the horizontal streaks. Based on their orbits, sungrazer comets are...
  • Astronomy Picture of the Day -- Red Moon Rising [ cue the Creedence ]

    12/16/2011 3:46:07 PM PST · by SunkenCiv · 16 replies
    NASA ^ | December 16, 2011 | (see photo credit)
    Explanation: This surreal, wintry scene is a composite picture recorded on December 10 as the Moon rose behind the Zagros Mountains of Iran. A total lunar eclipse was already in progress. The image combines nearly 500 successive frames taken over 1.5 hours beginning in twilight as the eclipsed Moon steadily climbed above the rugged landscape. The reddened lunar disk and deep blue twilight make for a striking contrast, yet the contrasting colors have the same root cause. The eclipsed Moon is red because the Earth's umbral shadow is suffused with a faint red light. The ruddy illumination is from all...
  • Astronomy Picture of the Day -- The Umbra of Earth

    12/14/2011 9:29:58 PM PST · by SunkenCiv · 10 replies
    NASA ^ | December 15, 2011 | (see photo credit)
    Explanation: The dark, inner shadow of planet Earth is called the umbra. Shaped like a cone extending into space, it has a circular cross section most easily seen during a lunar eclipse. For example, last Saturday the Full Moon slid across the southern half of Earth's umbral shadow, entertaining moonwatchers around much of the planet. In the total phase of the eclipse, the Moon was completely within the umbra for 51 minutes. Recorded from Beijing, China, this composite eclipse image uses successive pictures from totality (center) and partial phases to trace out a large part of the umbra's curved edge....
  • Astronomy Picture of the Day -- A Lunar Eclipse Over an Indian Peace Pagoda

    12/14/2011 4:33:28 PM PST · by SunkenCiv · 15 replies
    NASA ^ | December 14, 2011 | (see photo credit)
    Explanation: Our Moon turned red last week. The reason was that during December 10, a total lunar eclipse occurred. The above digitally superimposed image mosaic captured the Moon many times during the eclipse, from before the Moon entered Earth's shadow until after the Moon exited. The image sequence was recorded over a Shanti Stupa Peace Pagota near the center of New Delhi, India. The red tint of the eclipsed Moon was created by sunlight first passing through the Earth's atmosphere, which preferentially scatters blue light (making the sky blue) but passes and refracts red light, before reflecting back off the...
  • Astronomy Picture of the Day -- In the Vicinity of the Cone Nebula

    12/13/2011 5:28:15 PM PST · by SunkenCiv · 9 replies
    NASA ^ | December 13, 2011 | (see photo credit)
    Explanation: Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars. The brightest star on the right of the above picture is S Mon, while the region just below it has been nicknamed the Fox Fur Nebula for its color and structure. The blue glow directly surrounding S Mon results from reflection, where neighboring dust reflects light from the bright star. The red glow that encompasses the whole region results not only...
  • Astronomy Picture of the Day -- An Unusual Vein of Deposited Rock on Mars

    12/12/2011 12:37:10 AM PST · by SunkenCiv · 11 replies
    NASA ^ | December 12, 2011 | (see photo credit)
    Explanation: What could create this unusual vein of rock on Mars? A leading hypothesis is that this thin rock layer dubbed "Homestake" was deposited by a running liquid -- like most mineral veins are here on Earth. And the running liquid of choice is water. Therefore, this mineral streak -- rich in calcium and sulfur -- is the latest in the growing body of evidence that part of Mars had a watery past. This, in turn, increases the speculation that Mars was once hospitable to life. Pictured above is a vista taken near the western rim of Endeavour Crater by...
  • Astronomy Picture of the Day -- Searching for Meteorites in Antarctica

    12/11/2011 11:29:29 AM PST · by SunkenCiv · 23 replies
    NASA ^ | December 11, 2011 | (see photo credit)
    Explanation: Where is the best place on Earth to find meteorites? Although meteors fall all over the world, they usually just sink to the bottom of an ocean, are buried by shifting terrain, or are easily confused with terrestrial rocks. At the bottom of the Earth, however, in East Antarctica, huge sheets of blue ice remain pure and barren. When traversing such a sheet, a dark rock will stick out. These rocks have a high probability of being true meteorites -- likely pieces of another world. An explosion or impact might have catapulted these meteorites from the Moon, Mars, or...
  • Astronomy Picture of the Day -- Vesta Rocks

    12/11/2011 11:25:13 AM PST · by SunkenCiv · 7 replies
    NASA ^ | December 10, 2011 | (see photo credit)
    Explanation: These colorful images are of thin slices of meteorites viewed through a polarizing microscope. Part of the group classified as HED meteorites for their mineral content (Howardite, Eucrite, Diogenite), they likely fell to Earth from 4 Vesta, the mainbelt asteroid currently being explored by NASA's Dawn spacecraft. Why are they thought to be from Vesta? Because the HED meteorites have visible and infrared spectra that match the spectrum of that small world. The hypothesis of their origin on Vesta is also consistent with data from Dawn's ongoing observations. Excavated by impacts, the diogenites shown here would have originated deep...
  • Astronomy Picture of the Day -- Eclipsed Moon in the Morning

    12/09/2011 2:46:01 PM PST · by SunkenCiv · 8 replies
    NASA ^ | December 09, 2011 | (see photo credit)
    Explanation: Tomorrow, December 10, the Full Moon will slide through planet Earth's shadow in a total lunar eclipse. The entire eclipse sequence, including 51 minutes of totality, will be visible from Asia and Australia, but moonwatchers in Europe and Africa will miss out on the beginning partial phases because for them, the eclipse will start before moonrise. In central and western North America the earlier phases of the eclipse will be in progress as the Moon sets. In fact, while those in the east will miss out, North Americans far enough west could see a scene very much like this...
  • Astronomy Picture of the Day -- Sh2-239: Celestial Impasto

    12/08/2011 5:58:00 PM PST · by SunkenCiv · 14 replies
    NASA ^ | December 08, 2011 | (see photo credit)
    Explanation: The cosmic brush of star formation composed this alluring mix of dust and dark nebulae. Cataloged as Sh2-239 and LDN 1551, the region lies near the southern end of the Taurus molecular cloud complex some 450 light-years distant. Stretching for nearly 3 light-years, the canvas abounds with signs of embedded young stellar objects driving dynamic outflows into the surrounding medium. Included near the center of the frame, a compact, tell-tale red jet of shocked hydrogen gas is near the position of infrared source IRS5, known to be a system of protostars surrounded by dust disks. Just below it are...
  • Astronomy Picture of the Day -- Kepler 22b: An Almost Earth Orbiting an Almost Sun

    12/06/2011 11:17:56 PM PST · by SunkenCiv · 29 replies
    NASA ^ | December 07, 2011 | (see photo credit)
    Explanation: It's the closest match to Earth that has yet been found. Recently discovered planet Kepler 22b has therefore instantly become the best place to find life outside our Solar System. The planet's host star, Kepler 22, is actually slightly smaller and cooler than the Sun, and lies 600 light-years from Earth toward the constellation of the Swan (Cygnus). The planet, Kepler 22b, is over twice the radius of the Earth and orbits slightly closer in, but lies in the habitable zone where liquid water could exist on the surface. Pictured above is an artist's depiction of how Kepler 22b...
  • Astronomy Picture of the Day -- Jupiter Rotation Movie from Pic du Midi

    12/06/2011 2:29:36 PM PST · by SunkenCiv · 6 replies
    NASA ^ | December 06, 2011 | (see photo credit)
    Explanation: Observe the graceful twirl of the Solar System's largest planet. Many interesting features of Jupiter's enigmatic atmosphere, including dark bands and light zones, can be followed in detail. A careful inspection will reveal that central clouds rotate slightly faster than clouds toward the poles. The famous Great Red Spot is visible at first but soon rotates out of view, only to return near the movie's end. Other smaller storm systems ocassionally appear. As large as Jupiter is, it rotates in only 10 hours. Our small Earth, by comparison, takes 24 hours to complete a spin cycle. The above high-resolution...
  • Astronomy Picture of the Day -- A Memorable Aurora Over Norway

    12/05/2011 8:33:46 AM PST · by SunkenCiv · 7 replies
    NASA ^ | December 05, 2011 | (see photo credit)
    Explanation: It was one of the most memorable auroras of the season. There was green light, red light, and sometimes a mixture of the two. There were multiple rays, distinct curtains, and even an auroral corona. It took up so much of the sky. In the background were stars too numerous to count, in the foreground a friend trying to image the same sight. The scene was captured with a fisheye lens around and above Tromsø, Norway, last month. With the Sun becoming more active, next year might bring even more spectacular aurora.
  • Astronomy Picture of the Day -- Light Echoes from V838 Mon

    12/03/2011 9:56:40 PM PST · by SunkenCiv · 20 replies
    NASA ^ | December 04, 2011 | (see photo credit)
    Explanation: For reasons unknown, star V838 Mon's outer surface suddenly greatly expanded with the result that it became the brightest star in the entire Milky Way Galaxy in January 2002. Then, just as suddenly, it faded. A stellar flash like this has never been seen before. It's true that supernovae and novae expel matter out into space. But while the V838 Mon flash appears to expel material into space, what is seen here is actually an outwardly moving light echo of the bright flash. In a light echo, light from the flash is reflected by successively more distant rings in...
  • Astronomy Picture of the Day -- As Above, So Below

    12/03/2011 3:53:40 AM PST · by SunkenCiv · 12 replies
    NASA ^ | December 03, 2011 | (see photo credit)
    Explanation: A single, long exposure captured these star trails above a remarkably colorful sea of clouds. As seen from Medvednica mountain, the surrounding peaks and lights illuminating the clouds from below are north of Zagreb, Croatia. Near the center of the also colorful star trail arcs, the North Celestial Pole is off the upper right edge of the frame. Even though this is the age of the digital camera, the well composed skyscape was recorded using color slide film in a medium format camera. The dreamlike scene's starry sky and ephemeral ocean could be reminiscent of an older age still,...