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  • Astronomy Picture of the Day -- Pillars and Jets in the Pelican Nebula

    03/04/2015 3:02:06 PM PST · by SunkenCiv · 8 replies
    NASA ^ | March 04, 2015 | (see photo credit)
    Explanation: What dark structures arise from the Pelican Nebula? Visible as a bird-shaped nebula toward the constellation of a bird (Cygnus, the Swan), the Pelican Nebula is a place dotted with newly formed stars but fouled with dark dust. These smoke-sized dust grains formed in the cool atmospheres of young stars and were dispersed by stellar winds and explosions. Impressive Herbig-Haro jets are seen emitted by a star on the right that is helping to destroy the light year-long dust pillar that contains it. The featured image was scientifically-colored to emphasize light emitted by small amounts of ionized nitrogen, oxygen,...
  • Astronomy Picture of the Day -- A Dust Devil on Mars

    03/03/2015 3:39:47 AM PST · by SunkenCiv · 5 replies
    NASA ^ | March 03, 2015 | (see photo credit)
    Explanation: It was late in the northern martian spring when the HiRISE camera onboard the Mars Reconnaissance Orbiter spied this local denizen. Tracking across the flat, dust-covered Amazonis Planitia in 2012, the core of this whirling dust devil is about 140 meters in diameter. Lofting dust into the thin martian atmosphere, its plume reaches about 20 kilometers above the surface. Common to this region of Mars, dust devils occur as the surface is heated by the Sun, generating warm, rising air currents that begin to rotate. Tangential wind speeds of up to 110 kilometers per hour are reported for dust...
  • Astronomy Picture of the Day -- Lenticular Cloud, Moon, Mars, Venus

    03/02/2015 4:39:52 AM PST · by SunkenCiv · 21 replies
    NASA ^ | March 02, 2015 | (see photo credit)
    Explanation: It is not every day that such an interesting cloud photobombs your image. The original plan was to photograph a rare angular conjunction of Mars and Venus that occurred a week and a half ago, with the added bonus of a crescent Moon and the International Space Station (ISS) both passing nearby. Unfortunately, on Madeira Island, Portugal, this event was clouded out. During the next day, however, a spectacular lenticular cloud appeared before sunset, so the industrious astrophotographer quickly formulated a new plan. A close look at the resulting image reveals the Moon visible toward the left of the...
  • Astronomy Picture of the Day -- Inside the Coma Cluster of Galaxies

    03/01/2015 8:36:27 AM PST · by SunkenCiv · 3 replies
    NASA ^ | March 01, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- Moon-Venus-Mars Skyline

    02/28/2015 6:26:34 AM PST · by SunkenCiv · 5 replies
    NASA ^ | February 28, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- Long Lovejoy and Little Dumbbell

    02/27/2015 4:58:58 AM PST · by SunkenCiv · 2 replies
    NASA ^ | February 27, 2015 | (see photo credit)
    Explanation: 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....
  • Astronomy Picture of the Day -- Love and War by Moonlight

    02/26/2015 6:11:35 AM PST · by SunkenCiv · 5 replies
    NASA ^ | February 26, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- The Rosette Nebula in Hydrogen and Oxygen

    02/25/2015 5:25:27 AM PST · by SunkenCiv · 4 replies
    NASA ^ | February 25, 2015 | (see photo credit)
    Explanation: 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,...
  • Astronomy Picture of the Day -- Unusual Plumes Above Mars

    02/24/2015 2:18:41 PM PST · by SunkenCiv · 21 replies
    NASA ^ | February 24, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- The Milky Way Over the Arizona Toadstools

    02/23/2015 4:01:33 AM PST · by SunkenCiv · 9 replies
    NASA ^ | February 23, 2015 | (see photo credit)
    Explanation: 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,...
  • Astronomy Picture of the Day -- The Dark River to Antares

    02/22/2015 8:59:45 AM PST · by SunkenCiv · 6 replies
    NASA ^ | February 22, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- 45 Days in the Sun

    02/21/2015 8:26:45 AM PST · by SunkenCiv · 25 replies
    NASA ^ | February 21, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- An Evening Sky Conjunction

    02/20/2015 2:29:54 PM PST · by SunkenCiv · 11 replies
    NASA ^ | February 20, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- Palomar 12

    02/19/2015 5:27:30 AM PST · by SunkenCiv · 6 replies
    NASA ^ | February 19, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- Dark Craters and Bright Spots Revealed on Asteroid Ceres

    02/19/2015 5:22:59 AM PST · by SunkenCiv · 14 replies
    NASA ^ | February 18, 2015 | (see photo credit)
    Explanation: 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...
  • Astronomy Picture of the Day -- Fibrils Flower on the Sun

    02/17/2015 5:31:12 AM PST · by SunkenCiv · 3 replies
    NASA ^ | February 17, 2015 | (see photo credit)
    Explanation: When does the Sun look like a flower? In a specific color of red light emitted by hydrogen, as featured here, some regions of the solar chromosphere may resemble a rose. The color-inverted image was taken in 2014 October and shows active solar region 2177. The petals dominating the frame are actually magnetically confined tubes of hot plasma called fibrils, some of which extend longer the diameter of the Earth. In the central region many of these fibrils are seen end-on, while the surrounding regions are typically populated with curved fibrils. When seen over the Sun's edge, these huge...
  • Astronomy Picture of the Day -- M106: A Spiral Galaxy with a Strange Center

    02/16/2015 1:52:06 AM PST · by SunkenCiv · 8 replies
    NASA ^ | February 16, 2015 | (see photo credit)
    Explanation: What's happening at the center of spiral galaxy M106? A swirling disk of stars and gas, M106's appearance is dominated by blue spiral arms and red dust lanes near the nucleus, as shown in the featured image. The core of M106 glows brightly in radio waves and X-rays where twin jets have been found running the length of the galaxy. An unusual central glow makes M106 one of the closest examples of the Seyfert class of galaxies, where vast amounts of glowing gas are thought to be falling into a central massive black hole. M106, also designated NGC 4258,...
  • Astronomy Picture of the Day -- Two Hours Before Neptune

    02/15/2015 10:21:38 AM PST · by SunkenCiv · 7 replies
    NASA ^ | February 15, 2015 | (see photo credit)
    Explanation: Two hours before closest approach to Neptune in 1989, the Voyager 2 robot spacecraft snapped this picture. Clearly visible for the first time were long light-colored cirrus-type clouds floating high in Neptune's atmosphere. Shadows of these clouds can even be seen on lower cloud decks. Most of Neptune's atmosphere is made of hydrogen and helium, which is invisible. Neptune's blue color therefore comes from smaller amounts of atmospheric methane, which preferentially absorbs red light. Neptune has the fastest winds in the Solar System, with gusts reaching 2000 kilometers per hour. Speculation holds that diamonds may be created in the...
  • Astronomy Picture of the Day -- Solar System Portrait

    02/14/2015 5:10:04 AM PST · by SunkenCiv · 7 replies
    NASA ^ | February 14, 2015 | (see photo credit)
    Explanation: On another Valentine's Day 25 years ago, cruising four billion miles from the Sun, the Voyager 1 spacecraft looked back one last time to make this first ever Solar System family portrait. The complete portrait is a 60 frame mosaic made from a vantage point 32 degrees above the ecliptic plane. In it, Voyager's wide angle camera frames sweep through the inner Solar System at the left, linking up with gas giant Neptune, the Solar System's outermost planet, at the far right. Positions for Venus, Earth, Jupiter, Saturn, Uranus, and Neptune are indicated by letters, while the Sun is...
  • Astronomy Picture of the Day -- Aurora on Ice

    02/13/2015 5:49:51 AM PST · by SunkenCiv · 5 replies
    NASA ^ | February 13, 2015 | (see photo credit)
    Explanation: Not from a snowglobe, this expansive fisheye view of ice and sky was captured on February 1, from Jökulsárlón Beach, southeast Iceland, planet Earth. Chunks of glacial ice on the black sand beach glisten in the light of a nearly full moon surrounded by a shining halo. The 22 degree lunar halo itself is created by ice crystals in high, thin clouds refracting the moonlight. Despite the bright moonlight, curtains of aurora still dance through the surreal scene. In early February, their activity was triggered by Earth's restless magnetosphere and the energetic wind from a coronal hole near the...
  • Astronomy Picture of the Day -- Exploring the Antennae

    02/12/2015 6:29:51 AM PST · by SunkenCiv · 8 replies
    NASA ^ | February 12, 2015 | (see photo credit)
    Explanation: Some 60 million light-years away in the southerly constellation Corvus, two large galaxies are colliding. The stars in the two galaxies, cataloged as NGC 4038 and NGC 4039, very rarely collide in the course of the ponderous cataclysm, lasting hundreds of millions of years. But their large clouds of molecular gas and dust often do, triggering furious episodes of star formation near the center of the cosmic wreckage. Spanning about 500 thousand light-years, this stunning composited view also reveals new star clusters and matter flung far from the scene of the accident by gravitational tidal forces. The remarkable collaborative...
  • Astronomy Picture of the Day -- M100: A Grand Design Spiral Galaxy

    02/11/2015 4:25:57 AM PST · by SunkenCiv · 5 replies
    NASA ^ | February 11, 2015 | (see photo credit)
    Explanation: Majestic on a truly cosmic scale, M100 is appropriately known as a grand design spiral galaxy. It is a large galaxy of over 100 billion stars with well-defined spiral arms that is similar to our own Milky Way Galaxy. One of the brightest members of the Virgo Cluster of galaxies, M100 (alias NGC 4321) is 56 million light-years distant toward the constellation of Berenice's Hair (Coma Berenices). This Hubble Space Telescope image of M100 was made in 2006 and reveals bright blue star clusters and intricate winding dust lanes which are hallmarks of this class of galaxies. Studies of...
  • Astronomy Picture of the Day -- An Extremely Long Filament on the Sun

    02/10/2015 8:06:12 AM PST · by SunkenCiv · 11 replies
    NASA ^ | February 10, 2015 | (see photo credit)
    Explanation: Yesterday, the Sun exhibited one of the longest filaments ever recorded. It may still be there today. Visible as the dark streak just below the center in the featured image, the enormous filament extended across the face of the Sun a distance even longer than the Sun's radius -- over 700,000 kilometers. A filament is actually hot gas held aloft by the Sun's magnetic field, so that viewed from the side it would appear as a raised prominence. The featured image shows the filament in light emitted by hydrogen and therefore highlights the Sun's chromosphere. Sun-following telescopes including NASA's...
  • Astronomy Picture of the Day -- Layered Rocks near Mount Sharp on Mars

    02/09/2015 6:31:47 AM PST · by SunkenCiv · 24 replies
    NASA ^ | February 09, 2015 | (see photo credit)
    Explanation: What caused these Martian rocks to be layered? The leading hypothesis is an ancient Martian lake that kept evaporating and refilling over 10 million years -- but has now remained dry and empty of water for billions of years. The featured image, taken last November by the robotic Curiosity rover, shows one-meter wide Whale Rock which is part of the Pahrump Hills outcrop at the base of Mount Sharp. Also evident in the image is cross-bedding -- rock with angled layers -- which were likely facilitated by waves of sand. Curiosity continues to find many layered rocks like this...
  • Astronomy Picture of the Day -- Carina Nebula Dust Pillar

    02/08/2015 10:30:15 AM PST · by SunkenCiv · 6 replies
    NASA ^ | February 08, 2015 | (see photo credit)
    Explanation: This cosmic pillar of gas and dust is nearly two light-years wide. The structure lies within one of our galaxy's largest star forming regions, the Carina Nebula, shining in southern skies at a distance of about 7,500 light-years. The pillar's convoluted outlines are shaped by the winds and radiation of Carina's young, hot, massive stars. But the interior of the cosmic pillar itself is home to stars in the process of formation. In fact, a penetrating infrared view shows the pillar is dominated by two, narrow, energetic jets blasting outward from a still hidden infant star. The above featured...
  • Astronomy Picture of the Day -- An Aurora of Marbles

    02/07/2015 5:07:47 AM PST · by SunkenCiv · 10 replies
    NASA ^ | February 07, 2015 | (see photo credit)
    Explanation: It looks like a fine collection of aggies. But this grid of embedded swirls and streaks actually follows the dramatic development of planet Earth's auroral substorms. The sequence of over 600 horizon-to-horizon fisheye images was taken over a 2 hour period near the artic circle in March of 2012 from Lapland, northern Sweden. It begins at upper left in evening twilight and ends at lower right, covering two activity peaks with bright coronae forming overhead. While exploring space between Earth and Moon, NASA's fleet of THEMIS spacecraft discovered that these explosions of auroral activity are driven by sudden releases...
  • Astronomy Picture of the Day -- Jupiter Triple-Moon Conjunction

    02/06/2015 4:18:54 AM PST · by SunkenCiv · 8 replies
    NASA ^ | February 06, 2015 | (see photo credit)
    Explanation: Our solar system's ruling giant planet Jupiter and 3 of its 4 large Galilean moons are captured in this single Hubble snapshot from January 24. Crossing in front of Jupiter's banded cloud tops Europa, Callisto, and Io are framed from lower left to upper right in a rare triple-moon conjunction. Distinguishable by colors alone icy Europa is almost white, Callisto's ancient cratered surface looks dark brown, and volcanic Io appears yellowish. The transiting moons and moon shadows can be identified by sliding your cursor over the image, or following this link. Remarkably, two small, inner Jovian moons, Amalthea and...
  • Astronomy Picture of the Day -- A Fox Fur, a Unicorn, and a Christmas Tree

    02/06/2015 4:16:35 AM PST · by SunkenCiv · 1 replies
    NASA ^ | January 05, 2015 | (see photo credit)
    Explanation: What do the following things have in common: a cone, the fur of a fox, and a Christmas tree? Answer: they all occur in the constellation of the unicorn (Monoceros). Pictured as a star forming region and cataloged as NGC 2264, the complex jumble of cosmic gas and dust is about 2,700 light-years distant and mixes reddish emission nebulae excited by energetic light from newborn stars with dark interstellar dust clouds. Where the otherwise obscuring dust clouds lie close to the hot, young stars they also reflect starlight, forming blue reflection nebulae. The image spans about the diameter of...
  • Astronomy Picture of the Day -- M104: The Sombrero Galaxy

    02/05/2015 2:38:04 PM PST · by SunkenCiv · 22 replies
    NASA ^ | February 05, 2015 | (see photo credit)
    Explanation: The striking spiral galaxy M104 is famous for its nearly edge-on profile featuring a broad ring of obscuring dust lanes. Seen in silhouette against an extensive bulge of stars, the swath of cosmic dust lends a broad brimmed hat-like appearance to the galaxy suggesting the more popular moniker, The Sombrero Galaxy. Hubble Space Telescope and ground-based Subaru data have been reprocessed with amateur color image data to create this sharp view of the well-known galaxy. The processing results in a natural color appearance and preserves details often lost in overwhelming glare of M104's bright central bulge when viewed with...
  • Astronomy Picture of the Day -- Stars, Sprites, Clouds, Auroras

    02/04/2015 2:03:21 PM PST · by SunkenCiv · 12 replies
    NASA ^ | February 04, 2015 | (see photo credit)
    Explanation: What are those red streaks in the sky? While photographing unexpected auroras over a distant thunderstorm, something extraordinary happened: red sprites. This brief instance of rarely imaged high-altitude lightning flashed so bright that it was witnessed by several people independently. Pictured over Minnesota, USA in May 2013, these red sprites likely followed an extremely powerful low-altitude conventional lightning bolt. Captured in the featured frame are a house and electrical pole in the foreground, thick clouds in the lower atmosphere, a lightning storm on the horizon, distant red sprites and green aurora in the upper atmosphere, and distant stars from...
  • Astronomy Picture of the Day -- Jets from Comet Churyumov-Gerasimenko

    02/03/2015 6:44:09 AM PST · by SunkenCiv · 6 replies
    NASA ^ | February 03, 2015 | (see photo credit)
    Explanation: Where do comet tails come from? Although it is common knowledge that comet tails and comas originate from comet nuclei, exactly how that happens is an active topic of research. One of the best images yet of emerging jets is shown in the featured image, taken last November by the robotic Rosetta spacecraft in orbit around the Comet 67P/Churyumov-Gerasimenko (Comet CG), and released last month. The overexposed picture shows plumes of gas and dust escaping numerous places from the Comet CG's nucleus as it nears the Sun and heats up. Although Comet CG is currently further out from the...
  • Astronomy Picture of the Day -- Titan Seas Reflect Sunlight

    02/02/2015 7:29:37 AM PST · by SunkenCiv · 16 replies
    NASA ^ | February 02, 2015 | (see photo credit)
    Explanation: Why would the surface of Titan light up with a blinding flash? The reason: a sunglint from liquid seas. Saturn's moon Titan has numerous smooth lakes of methane that, when the angle is right, reflect sunlight as if they were mirrors. Pictured here in false-color, the robotic Cassini spacecraft orbiting Saturn imaged the cloud-covered Titan last summer in different bands of cloud-piercing infrared light. This specular reflection was so bright it saturated one of Cassini's infrared cameras. Although the sunglint was annoying -- it was also useful. The reflecting regions confirm that northern Titan houses a wide and complex...
  • Astronomy Picture of the Day -- NGC 4676: When Mice Collide

    02/01/2015 2:12:17 AM PST · by SunkenCiv · 7 replies
    NASA ^ | February 01, 2015 | (see photo credit)
    Explanation: These two mighty galaxies are pulling each other apart. Known as the "Mice" because they have such long tails, each spiral galaxy has likely already passed through the other. The long tails are created by the relative difference between gravitational pulls on the near and far parts of each galaxy. Because the distances are so large, the cosmic interaction takes place in slow motion -- over hundreds of millions of years. NGC 4676 lies about 300 million light-years away toward the constellation of Bernice's Hair (Coma Berenices) and are likely members of the Coma Cluster of Galaxies. The above...
  • Astronomy Picture of the Day -- Yellow Balls in W33

    02/01/2015 2:09:51 AM PST · by SunkenCiv · 5 replies
    NASA ^ | January 31, 2015 | (see photo credit)
    Explanation: Infrared wavelengths of 3.6, 8.0, and 24.0 microns observed by the Spitzer Space Telescope are mapped into visible colors red, green, and blue in this striking image. The cosmic cloud of gas and dust is W33, a massive starforming complex some 13,000 light-years distant, near the plane of our Milky Way Galaxy. So what are all those yellow balls? Citizen scientists of the web-based Milky Way Project found the features they called yellow balls as they scanned many Spitzer images and persistently asked that question of researchers. Now there is an answer. The yellow balls in Spitzer images are...
  • Astronomy Picture of the Day -- A Night at Poker Flat

    01/30/2015 5:29:01 AM PST · by SunkenCiv · 3 replies
    NASA ^ | January 30, 2015 | (see photo credit)
    Explanation: Four NASA suborbital sounding rockets leapt into the night on January 26, from the University of Alaska's Poker Flat Research Range. This time lapse composite image follows all four launches of the small, multi-stage rockets to explore winter's mesmerizing, aurora-filled skies. During the exposures, stars trailed around the North Celestial Pole, high above the horizon at the site 30 miles north of Fairbanks, Alaska. Lidar, beams of pulsed green lasers, also left traces through the scene. Operating successfully, the payloads lofted were two Mesosphere-Lower Thermosphere Turbulence Experiments (M-TeX) and two Mesospheric Inversion-layer Stratified Turbulence (MIST) experiments, creating vapor trails...
  • Astronomy Picture of the Day -- Close Encounter with M44

    01/29/2015 9:04:07 AM PST · by SunkenCiv · 4 replies
    NASA ^ | January 29, 2015 | (see photo credit)
    Explanation: On Monday, January 26, well-tracked asteroid 2004 BL86 made its closest approach, a mere 1.2 million kilometers from our fair planet. That's about 3.1 times the Earth-Moon distance or 4 light-seconds away. Moving quickly through Earth's night sky, it left this streak in a 40 minute long exposure on January 27 made from Piemonte, Italy. The remarkably pretty telescopic field of view includes M44, also known as the Beehive or Praesepe star cluster in Cancer. Of course, its close encounter with M44 is only an apparent one, with the cluster nearly along the same line-of-sight to the near-earth asteroid....
  • Astronomy Picture of the Day -- Comet Lovejoy in a Winter Sky

    01/29/2015 9:01:49 AM PST · by SunkenCiv · 6 replies
    NASA ^ | January 28, 2015 | (see photo credit)
    Explanation: Which of these night sky icons can you find in this beautiful and deep exposure of the northern winter sky? Skylights include the stars in Orion's belt, the Orion Nebula, the Pleiades star cluster, the bright stars Betelgeuse and Rigel, the California Nebula, Barnard's Loop, and Comet Lovejoy. The belt stars of Orion are nearly vertical in the central line between the horizon and the image center, with the lowest belt star obscured by the red glowing Flame Nebula. To the belt's left is the red arc of Barnard's Loop followed by the bright orange star Betelgeuse, while to...
  • Astronomy Picture of the Day -- Our Galaxy's Magnetic Field from Planck

    01/27/2015 8:31:28 AM PST · by SunkenCiv · 8 replies
    NASA ^ | January 27, 2015 | (see photo credit)
    Explanation: What does the magnetic field of our Galaxy look like? It has long been known that a modest magnetic field pervades our Milky Way Galaxy because it is seen to align small dust grains that scatter background light. Only recently, however, has the Sun-orbiting Planck satellite made a high-resolution map of this field. Color coded, the 30-degree wide map confirms, among other things, that the Galaxy's interstellar magnetism is strongest in the central disk. The rotation of charged gas around the Galactic center creates this magnetism, and it is hypothesized that viewed from the top, the Milky Way's magnetic...
  • Astronomy Picture of the Day -- The Milky Way over the Seven Strong Men Rock Formations

    01/27/2015 8:27:56 AM PST · by SunkenCiv · 7 replies
    NASA ^ | January 26, 2015 | (see photo credit)
    Explanation: You may have heard of the Seven Sisters in the sky, but have you heard about the Seven Strong Men on the ground? Located just west of the Ural Mountains, the unusual Manpupuner rock formations are one of the Seven Wonders of Russia. How these ancient 40-meter high pillars formed is yet unknown. The persistent photographer of this featured image battled rough terrain and uncooperative weather to capture these rugged stone towers in winter at night, being finally successful in February of last year. Utilizing the camera's time delay feature, the photographer holds a flashlight in the foreground near...
  • Astronomy Picture of the Day -- A Twisted Solar Eruptive Prominence

    01/25/2015 1:20:36 AM PST · by SunkenCiv · 9 replies
    NASA ^ | January 25, 2015 | (see photo credit)
    Explanation: Ten Earths could easily fit in the "claw" of this seemingly solar monster. The monster, actually a huge eruptive prominence, is seen moving out from our Sun in this condensed half-hour time-lapse sequence. This large prominence, though, is significant not only for its size, but its shape. The twisted figure eight shape indicates that a complex magnetic field threads through the emerging solar particles. Differential rotation of gas just inside the surface of the Sun might help account for the surface explosion. The five frame sequence was taken in early 2000 by the Sun-orbiting SOHO satellite. Although large prominences...
  • Astronomy Picture of the Day -- Light from Cygnus A

    01/24/2015 12:59:30 PM PST · by SunkenCiv · 11 replies
    NASA ^ | January 24, 2015 | (see photo credit)
    Explanation: Celebrating astronomy in this International Year of Light, the detailed image reveals spectacular active galaxy Cygnus A in light across the electromagnetic spectrum. Incorporating X-ray data ( blue) from the orbiting Chandra Observatory, Cygnus A is seen to be a prodigious source of high energy x-rays. But it is actually more famous at the low energy end of the electromagnetic spectrum. One of the brightest celestial sources visible to radio telescopes, at 600 million light-years distant Cygnus A is the closest powerful radio galaxy. Radio emission ( red) extends to either side along the same axis for nearly 300,000...
  • Astronomy Picture of the Day -- Interior View [space station]

    01/23/2015 3:57:31 AM PST · by SunkenCiv · 7 replies
    NASA ^ | January 23, 2015 | (see photo credit)
    Explanation: Some prefer windows, and these are the best available on board the International Space Station. Taken on January 4, this snapshot from inside the station's large, seven-window Cupola module also shows off a workstation for controlling Canadarm2. Used to grapple visiting cargo vehicles and assist astronauts during spacewalks, the robotic arm is just outside the window at the right. The Cupola itself is attached to the Earth-facing or nadir port of the station's Tranquility module, offering dynamic panoramas of our fair planet. Seen from the station's 90 minute long, 400 kilometer high orbit, Earth's bright limb is in view...
  • Astronomy Picture of the Day -- Launch to Lovejoy

    01/22/2015 11:42:36 AM PST · by SunkenCiv · 4 replies
    NASA ^ | January 22, 2015 | (see photo credit)
    Explanation: Blasting skyward an Atlas V rocket carrying a U.S. Navy satellite pierces a cloud bank in this starry night scene captured on January 20. On its way to orbit from Space Launch Complex 41, Cape Canaveral Air Force Station, planet Earth, the rocket streaks past brightest star Sirius, as seen from a dark beach at Canaveral National Seashore. Above the alpha star of Canis Major, Orion the Hunter strikes a pose familiar to northern winter skygazers. Above Orion is the V-shaped Hyades star cluster, head of Taurus the Bull, and farther still above Taurus it's easy to spot the...
  • Astronomy Picture of the Day -- The Complex Ion Tail of Comet Lovejoy

    01/21/2015 2:52:55 AM PST · by SunkenCiv · 6 replies
    NASA ^ | January 21, 2015 | (see photo credit)
    Explanation: What causes the structure in Comet Lovejoy's tail? Comet C/2014 Q2 (Lovejoy), which is currently at naked-eye brightness and near its brightest, has been showing an exquisitely detailed ion tail. As the name implies, the ion tail is made of ionized gas -- gas energized by ultraviolet light from the Sun and pushed outward by the solar wind. The solar wind is quite structured and sculpted by the Sun's complex and ever changing magnetic field. The effect of the variable solar wind combined with different gas jets venting from the comet's nucleus accounts for the tail's complex structure. Following...
  • Astronomy Picture of the Day -- Approaching Asteroid Ceres

    01/20/2015 5:55:25 AM PST · by SunkenCiv · 19 replies
    NASA ^ | January 20, 2015 | (see photo credit)
    Explanation: It is the largest asteroid in the asteroid belt -- what secrets does it hold? To find out, NASA has sent the robotic Dawn spacecraft to explore and map this cryptic 1,000-kilometer wide world: Ceres. Orbiting between Mars and Jupiter, Ceres is officially categorized as a dwarf planet but has never been imaged in detail. Featured here is a 20-frame video taken a week ago of Dawn's approach that now rivals even the best images of Ceres ever taken by the Hubble Space Telescope. The video shows enough surface definition to discern its 9-hour rotation period. On target to...
  • Astronomy Picture of the Day -- Infrared Orion from WISE

    01/18/2015 11:53:07 PM PST · by SunkenCiv · 20 replies
    NASA ^ | January 19, 2015 | (see photo credit)
    Explanation: The Great Nebula in Orion is an intriguing place. Visible to the unaided eye, it appears as a small fuzzy patch in the constellation of Orion. But this image, an illusory-color four-panel mosaic taken in different bands of infrared light with the Earth orbiting WISE observatory, shows the Orion Nebula to be a bustling neighborhood or recently formed stars, hot gas, and dark dust. The power behind much of the Orion Nebula (M42) is the stars of the Trapezium star cluster, seen near the center of the above wide field image. The orange glow surrounding the bright stars pictured...
  • Astronomy Picture of the Day -- The Galactic Core in Infrared

    01/18/2015 3:24:38 AM PST · by SunkenCiv · 14 replies
    NASA ^ | January 18, 2015 | (see photo credit)
    Explanation: What's happening at the center of our Milky Way Galaxy? To help find out, the orbiting Hubble and Spitzer space telescopes have combined their efforts to survey the region in unprecedented detail in infrared light. Milky Way's center because visible light is more greatly obscured by dust. The above image encompasses over 2,000 images from the Hubble Space Telescope's NICMOS taken in 2008. The image spans 300 by 115 light years with such high resolution that structures only 20 times the size of our own Solar System are discernable. Clouds of glowing gas and dark dust as well as...
  • Astronomy Picture of the Day -- Comet Lovejoy's Tail

    01/17/2015 8:42:18 AM PST · by SunkenCiv · 7 replies
    NASA ^ | January 17, 2015 | (see photo credit)
    Explanation: Sweeping north in planet Earth's sky, Comet Lovejoy's greenish coma and blue tinted ion tail stretched across this field of stars in the constellation Taurus on January 13. The inset at the upper left shows the 1/2 degree angular size of the full moon for scale. So Lovejoy's coma appears only a little smaller (but much fainter) than a full moon on the sky, and its tail is visible for over 4 degrees across the frame. That corresponds to over 5 million kilometers at the comet's estimated distance of 75 million kilometers from Earth. Blown by the solar wind,...
  • Astronomy Picture of the Day -- Huygens Lands on Titan [flashback]

    01/16/2015 5:24:30 AM PST · by SunkenCiv · 6 replies
    NASA ^ | January 16, 2015 | (see photo credit)
    Explanation: Delivered by Saturn-bound Cassini, ESA's Huygens probe touched down on the ringed planet's largest moon Titan, ten years ago on January 14, 2005. These panels show fisheye images made during its slow descent by parachute through Titan's dense atmosphere. Taken by the probe's descent imager/spectral radiometer instrument they range in altitude from 6 kilometers (upper left) to 0.2 kilometers (lower right) above the moon's surprisingly Earth-like surface of dark channels, floodplains, and bright ridges. But at temperatures near -290 degrees C, the liquids flowing across Titan's surface are methane and ethane, hydrocarbons rather than water. After making the most...
  • Astronomy Picture of the Day -- Venus and Mercury at Sunset

    01/15/2015 4:23:51 AM PST · by SunkenCiv · 7 replies
    NASA ^ | January 15, 2015 | (see photo credit)
    Explanation: Inner planets Venus and Mercury can never wander far from the Sun in Earth's sky. This week you've probably seen them both gathered near the western horizon just after sunset, a close conjunction of bright celestial beacons in the fading twilight. The pair are framed in this early evening skyview captured on January 13 from the ruins of Szarvasko Castle in northwestern Hungary. Above the silhouette of the landscape's prominent volcanic hill Venus is much the brighter, separated from Mercury by little more than the width of two Full Moons. On Friday, planet Earth's early morning risers will also...