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Keyword: astronomy

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  • Astronomy Picture of the Day -- Comet Lemmon near the South Celestial Pole

    02/07/2013 4:00:05 AM PST · by SunkenCiv · 13 replies
    NASA ^ | February 07, 2013 | (see photo credit)
    Explanation: Currently sweeping through southern skies, Comet Lemmon (C/2012 F6) was named for its discovery last year as part of the Mount Lemmon (Arizona) Survey. Brighter than expected but still just below naked-eye visibility, Comet Lemmon sports a stunning lime green coma and faint divided tail in this telescopic image from February 4. The greenish tint comes from the coma's diatomic C2 gas fluorescing in sunlight. Captured from an observatory near Sydney, Australia, the color composite is constructed from a series of individual exposures registered on the comet. Across the 1 degree wide field of view, the star trails are...
  • Astronomy Picture of the Day -- The Arms of M106

    02/06/2013 8:04:41 PM PST · by SunkenCiv · 5 replies
    NASA ^ | February 06, 2013 | (see photo credit)
    Explanation: The spiral arms of bright galaxy M106 sprawl through this remarkable multiframe portrait, composed of data from ground- and space-based telescopes. Also known as NGC 4258, M106 can be found toward the northern constellation Canes Venatici. The well-measured distance to M106 is 23.5 million light-years, making this cosmic scene about 80,000 light-years across. Typical in grand spiral galaxies, dark dust lanes, youthful blue star clusters, and pinkish star forming regions trace spiral arms that converge on the bright nucleus of older yellowish stars. But this detailed composite reveals hints of two anomalous arms that don't align with the more...
  • Astronomy Picture of the Day -- Mars: Shadow at Point Lake

    02/05/2013 5:05:14 PM PST · by SunkenCiv · 19 replies
    NASA ^ | February 05, 2013 | (see photo credit)
    Explanation: What if you saw your shadow on Mars and it wasn't human? Then you might be the robotic Curiosity rover currently exploring Mars. Curiosity landed in Gale Crater last August and has been busy looking for signs of ancient running water and clues that Mars could once have harbored life. Pictured above, Curiosity has taken a wide panorama that includes its own shadow in the direction opposite the Sun. The image was taken in November from a location dubbed Point Lake, although no water presently exists there. Curiosity has already discovered several indications of dried streambeds on Mars, and...
  • Astronomy Picture of the Day -- Namibian Nights

    02/04/2013 6:16:25 PM PST · by SunkenCiv · 5 replies
    NASA ^ | February 04, 2013 | (see photo credit)
    Explanation: Namibia has some of the darkest nights visible from any continent. It is therefore home to some of the more spectacular skyscapes, a few of which have been captured in the above time-lapse video. Visible at the movie start are unusual quiver trees perched before a deep starfield highlighted by the central band of our Milky Way Galaxy. This bright band of stars and gas appears to pivot around the celestial south pole as our Earth rotates. The remains of camel thorn trees are then seen against a sky that includes a fuzzy patch on the far right that...
  • Astronomy Picture of the Day -- L Ori and the Orion Nebula

    02/02/2013 9:25:36 PM PST · by SunkenCiv · 25 replies
    NASA ^ | February 03, 2013 | (see photo credit)
    Explanation: This esthetic close-up of cosmic clouds and stellar winds features LL Orionis, interacting with the Orion Nebula flow. Adrift in Orion's stellar nursery and still in its formative years, variable star LL Orionis produces a wind more energetic than the wind from our own middle-aged Sun. As the fast stellar wind runs into slow moving gas a shock front is formed, analogous to the bow wave of a boat moving through water or a plane traveling at supersonic speed. The small, arcing, graceful structure just above and left of center is LL Ori's cosmic bow shock, measuring about half...
  • Astronomy Picture of the Day -- Herschel's Andromeda

    02/02/2013 9:46:25 AM PST · by SunkenCiv · 5 replies
    NASA ^ | February 02, 2013 | (see photo credit)
    Explanation: This infrared view from the Herschel Space Observatory explores the Andromeda Galaxy, the closest large spiral galaxy to our own Milky Way. Only 2.5 million light-years distant, the famous island universe is also known to astronomers as M31. Andromeda spans over 200,000 light-years making it more the twice the size of the Milky Way. Shown in false color, the image data reveal the cool dust lanes and clouds that still shine in the infrared but are otherwise dark and opaque at visual wavelengths. Red hues near the galaxy's outskirts represent the glow of dust heated by starlight to a...
  • Astronomy Picture of the Day -- Atlas V Launches TDRS-K

    02/01/2013 5:09:21 PM PST · by SunkenCiv · 4 replies
    NASA ^ | February 01, 2013 | (see photo credit)
    Explanation: Beyond a fertile field of satellite communication antennas at Kennedy Space Center, an Atlas V rocket streaks into orbit in this long exposure photograph. In the thoughtfully composed image recorded on the evening of January 30, the antennas in the foreground bring to mind the rocket's payload, a Tracking and Data Relay Satellite (TDRS; sounds like TEE-dress). This TDRS-K is the first in a next-generation series adding to the constellation of NASA's communication satellites. Operating from geosynchronous orbit 22,300 miles (36,000 kilometers) above planet Earth, the network of TDRS satellites relays communications, data, and commands between spacecraft and ground...
  • Astronomy Picture of the Day -- NGC 4372 and the Dark Doodad

    01/31/2013 3:29:35 AM PST · by SunkenCiv · 11 replies
    NASA ^ | January 31, 2013 | (see photo credit)
    Explanation: The delightful Dark Doodad Nebula drifts through southern skies, a tantalizing target for binoculars in the constellation Musca, The Fly. The dusty cosmic cloud is seen against rich starfields just south of the prominent Coalsack Nebula and the Southern Cross. Stretching for about 3 degrees across this scene the Dark Doodad seems punctuated at its southern tip (lower left) by globular star cluster NGC 4372. Of course NGC 4372 roams the halo of our Milky Way Galaxy, a background object some 20,000 light-years away and only by chance along our line-of-sight to the Dark Doodad. The Dark Doodad's well...
  • Astronomy Picture of the Day -- Full Moon Silhouettes

    01/30/2013 4:35:44 AM PST · by SunkenCiv · 8 replies
    NASA ^ | January 30, 2013 | (see photo credit)
    Explanation: Have you ever watched the Moon rise? The slow rise of a nearly full moon over a clear horizon can be an impressive sight. One impressive moonrise was imaged two nights ago over Mount Victoria Lookout in Wellington, New Zealand. With detailed planning, an industrious astrophotographer placed a camera about two kilometers away and pointed it across the lookout to where the Moon would surely soon be making its nightly debut. The above single shot sequence is unedited and shown in real time -- it is not a time lapse. People on Mount Victoria Lookout can be seen in...
  • Astronomy Picture of the Day -- Apollo 16: Driving on the Moon

    01/30/2013 4:32:11 AM PST · by SunkenCiv · 18 replies
    NASA ^ | January 29, 2013 | (see photo credit)
    Explanation: What would it be like to drive on the Moon? You don't have to guess -- humans have actually done it. Pictured above, Apollo 16 astronauts John Young and Charles Duke recorded video during one such drive in 1972, with a digital version now available on the web. No matter which direction it headed, the Lunar Rover traveled a path literally covered with rocks and craters. The first half of the above video shows the rover zipping about a moonscape near 10 kilometers per hour, while the second half shows a dash-cam like view. The Lunar Rover was deployed...
  • Astronomy Picture of the Day -- In the Center of the Trifid Nebula

    01/28/2013 4:16:35 AM PST · by SunkenCiv · 10 replies
    NASA ^ | January 28, 2013 | (see photo credit)
    Explanation: Clouds of glowing gas mingle with dust lanes in the Trifid Nebula, a star forming region toward the constellation of the Archer (Sagittarius). In the center, the three prominent dust lanes that give the Trifid its name all come together. Mountains of opaque dust appear on the right, while other dark filaments of dust are visible threaded throughout the nebula. A single massive star visible near the center causes much of the Trifid's glow. The Trifid, also known as M20, is only about 300,000 years old, making it among the youngest emission nebulae known. The nebula lies about 9,000...
  • Astronomy Picture of the Day -- Comet McNaught Over Chile

    01/26/2013 9:52:07 PM PST · by SunkenCiv · 12 replies
    NASA ^ | January 27, 2013 | (see photo credit)
    Explanation: Comet McNaught of 2007 has been, so far, the most photogenic comet of our time. After making quite a show in the northern hemisphere in early 2007 January, the comet moved south and developed a long and unusual dust tail that dazzled southern hemisphere observers. In this image, Comet McNaught was captured above Santiago, Chile. The bright comet dominates on the left while part of its magnificent tail spreads across the entire frame. From this vantage point in the Andes Mountains, one looks up toward Comet McNaught and a magnificent sky, across at a crescent moon, and down on...
  • Astronomy Picture of the Day -- Alaskan Moondogs

    01/25/2013 9:53:01 PM PST · by SunkenCiv · 16 replies
    NASA ^ | January 26, 2013 | (see photo credit)
    Explanation: Moonlight illuminates a snowy scene in this night land and skyscape made on January 17 from Lower Miller Creek, Alaska, USA. Overexposed near the mountainous western horizon is the first quarter Moon itself, surrounded by an icy halo and flanked left and right by moondogs. Sometimes called mock moons, a more scientific name for the luminous apparations is paraselenae (plural). Analogous to a sundog or parhelion, a paraselene is produced by moonlight refracted through thin, hexagonal, plate-shaped ice crystals in high cirrus clouds. As determined by the crystal geometry, paraselenae are seen at an angle of 22 degrees or...
  • Astronomy Picture of the Day -- Matijevic Hill Panorama

    01/25/2013 3:44:48 AM PST · by SunkenCiv · 2 replies
    NASA ^ | January 25, 2013 | (see photo credit)
    Explanation: On January 25 (UT) 2004, the Opportunity rover fell to Mars, making today the 9th anniversary of its landing. After more than 3,200 sols (Mars solar days) the golf cart-sized robot from Earth is still actively exploring the Red Planet, though its original mission plan was for three months. Having driven some 35 kilometers (22 miles) from its landing site, Opportunity's panoramic camera recorded the segments of this scene, in November and December of last year. The digitally stitched panorama spans more than 210 degrees across the Matijevic Hill area along the western rim of Endeavour Crater. Features dubbed...
  • Astronomy Picture of the Day -- ISS and the Summer Milky Way

    01/24/2013 3:42:15 AM PST · by SunkenCiv · 7 replies
    NASA ^ | January 24, 2013 | (see photo credit)
    Explanation: Clouds on a summer night frame this sea and skyscape, recorded earlier this month near Buenos Aires, Argentina. But planet Earth's clouds are not the only clouds on the scene. Starry clouds and nebulae along the southern hemisphere's summer Milky Way arc above the horizon, including the dark Coal Sack near the Southern Cross and the tantalizing pinkish glow of the Carina Nebula. Both the Large (top center) and Small Magellanic Clouds are also in view, small galaxies in their own right and satellites of the Milky Way up to 200,000 light-years distant. Alpha star of the Carina constellation...
  • Astronomy Picture of the Day -- Nearby Spiral Galaxy NGC 4945

    01/23/2013 3:40:56 AM PST · by SunkenCiv · 7 replies
    NASA ^ | January 23, 2013 | (see photo credit)
    Explanation: Large spiral galaxy NGC 4945 is seen edge-on near the center of this cosmic galaxy portrait. In fact, NGC 4945 is almost the size of our own Milky Way Galaxy. Its own dusty disk, young blue star clusters, and pink star forming regions standout in the sharp, colorful telescopic image. About 13 million light-years distant toward the expansive southern constellation Centaurus, NGC 4945 is only about six times farther away than Andromeda, the nearest large spiral galaxy to the Milky Way. Though the galaxy's central region is largely hidden from view for optical telescopes, X-ray and infrared observations indicate...
  • Astronomy Picture of the Day -- The Cygnus Wall of Star Formation

    01/22/2013 9:02:41 PM PST · by SunkenCiv · 20 replies
    NASA ^ | January 22, 2013 | (see photo credit)
    Explanation: The North America nebula on the sky can do what the North America continent on Earth cannot -- form stars. Specifically, in analogy to the Earth-confined continent, the bright part that appears as Central America and Mexico is actually a hot bed of gas, dust, and newly formed stars known as the Cygnus Wall. The above image shows the star forming wall lit and eroded by bright young stars, and partly hidden by the dark dust they have created. The part of the North America nebula (NGC 7000) shown spans about 15 light years and lies about 1,500 light...
  • Astronomy Picture of the Day -- Huygens: Titan Descent Movie

    01/20/2013 9:49:52 PM PST · by SunkenCiv · 8 replies
    NASA ^ | January 21, 2013 | (see photo credit)
    Explanation: What would it look like to land on Saturn's moon Titan? The European Space Agency's Huygens probe set down on the Solar System's cloudiest moon in 2005, and a time-lapse video of its descent images was created. Huygens separated from the robotic Cassini spacecraft soon after it achieved orbit around Saturn in late 2004 and began approaching Titan. For two hours after arriving, Huygens plummeted toward Titan's surface, recording at first only the shrouded moon's opaque atmosphere. The computerized truck-tire sized probe soon deployed a parachute to slow its decent, pierced the thick clouds, and began transmitting images of...
  • Astronomy Picture of the Day -- The Antikythera Mechanism

    01/19/2013 9:15:30 PM PST · by SunkenCiv · 23 replies
    NASA ^ | January 20, 2013 | (see photo credit)
    Explanation: What is it? It was found at the bottom of the sea aboard an ancient Greek ship. Its seeming complexity has prompted decades of study, although some of its functions remained unknown. X-ray images of the device have confirmed the nature of the Antikythera mechanism, and discovered several surprising functions. The Antikythera mechanism has been discovered to be a mechanical computer of an accuracy thought impossible in 80 BC, when the ship that carried it sank. Such sophisticated technology was not thought to be developed by humanity for another 1,000 years. Its wheels and gears create a portable orrery...
  • Solar System Ice: Source of Earth's Water

    07/14/2012 6:12:51 AM PDT · by SunkenCiv · 19 replies
    Carnegie Institution ^ | Thursday, July 12, 2012 | unattributed
    Scientists have long believed that comets and, or a type of very primitive meteorite called carbonaceous chondrites were the sources of early Earth's volatile elements -- which include hydrogen, nitrogen, and carbon -- and possibly organic material, too. Understanding where these volatiles came from is crucial for determining the origins of both water and life on the planet. New research led by Carnegie's Conel Alexander focuses on frozen water that was distributed throughout much of the early Solar System, but probably not in the materials that aggregated to initially form Earth... It has been suggested that both comets and carbonaceous...