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Keyword: astronomy

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  • A Goofball Called Pluto

    05/26/2007 8:56:35 PM PDT · by SunkenCiv · 4 replies · 419+ views
    SpaceDaily ^ | May 18, 2007 | Bruce Moomaw
    "IAU presented the resolution to its General Assembly on August 16, giving the roughly 2500 attendees more than a week to discuss it. But the committee expected clear sailing...Instead, the '12-planet proposal' went down in flames. Critics objected that planets should also be defined by their orbital dynamics, not just by their size and shape. All eight 'major' planets, they pointed out, were massive enough to sweep up, fling away, or gravitationally control all the debris in their parts of the early solar sys[t]em, but Ceres and Pluto [and other candidate 'planets' among Kuiper Belt Objects] were not... the absurdity...
  • Demoted planet, dejected boy:A student pines for Pluto to be restored to its former planetary status

    11/05/2007 9:02:04 AM PST · by SunkenCiv · 8 replies · 66+ views
    Christian Science Monitor ^ | November 1, 2007 | Robert Klose
    I understood his travail. When I was a kid, I had a favorite planet. It seemed that all my friends did. Mine, for a reason I can no longer put my finger on, was Venus. I still recall a schoolyard fray in which I faced off against a kid who was ballyhooing the case for Jupiter as the "best" planet. The volume of recriminations rose to the point where a crowd gathered and one of the teachers had to separate us. Who knew that astronomy could stoke such passions? ...The thing is, like that long-ago schoolyard standoff pitting Venus against...
  • Interview with the IAU President on Pluto's Demotion

    09/11/2006 4:09:36 PM PDT · by KevinDavis · 6 replies · 178+ views
    space.com ^ | 09/11/06 | Sara Goudarzi
    Last month, Catherine Cesarsky became the president of the International Astronomical Union (IAU). Cesarsky, the first woman to hold this prestigious position, started her presidency at a time when many scientists are questioning IAU's recent decision to strip Pluto of its planetary status based on a vote of just 424 members at a meeting in Prague. Cesarsky served as the director general of the European Southern Observatory since 1999 and is famed for her research work in central areas of modern astrophysics. She also led the design and construction of the ISOCAM camera onboard the Infrared Space Observatory (ISO) of...
  • Experts' vote could mean demotion for Pluto

    08/13/2006 5:58:09 PM PDT · by SunkenCiv · 47 replies · 377+ views
    Rocky Mountain News ^ | August 12, 2006 | Jim Erickson
    News leaks about the planet definition began to spout late this week, as the authors prepared to present a draft resolution to the IAU's executive committee Sunday in Prague. The IAU is the official arbiter of all issues related to astronomical nomenclature. In a story that aired Thursday, unnamed sources told National Public Radio the proposed definition would include Pluto in a new class of small planets. A source also told the Rocky Mountain News on Thursday that a member of the seven-person definition panel said Pluto will remain a planet. IAU Vice President Bob Williams described the reports as...
  • Planetary Politics: Protecting Pluto

    09/09/2006 8:17:25 AM PDT · by SunkenCiv · 12 replies · 278+ views
    Space dot com ^ | 7 September 2006 | Edna DeVore
    Earlier this year, the BBC interviewed Mrs Venetia (Burney) Phair, the only living person to have named a planet... The IAU decision was political. Scientists voted to demote Pluto to the status of "dwarf planet." ...In California, of course, the real politicians found a reason for action in Pluto's demotion. While there are many more serious problems--over crowded schools and universities, decayed freeways, and the health care crisis, just to name a few—fifty-four of our esteemed elected officials found the time and energy for a Resolution that supports Pluto's status as a full-fledged planet. They call the IAU "mean-spirited" for...
  • New Planet Is Bigger Than Pluto

    02/01/2006 11:04:55 AM PST · by NormsRevenge · 42 replies · 500+ views
    AP on Yahoo ^ | 2/1/06 | Alicia Chang - ap
    LOS ANGELES - Scientists say they have confirmed that a so-called 10th planet discovered last year is bigger than Pluto, but that likely won't quell the debate over what makes a planet. The astronomers who spotted the icy, rocky body — informally called UB313 — had reported only a rough estimate of its size based on its brightness. But another group of researchers has come up with what is believed to be the first calculation of UB313's diameter. By measuring how much heat it radiates, German scientists led by Frank Bertoldi of the University of Bonn estimated that UB313 was...
  • Having Pups Over Pluto And The Planetary Misfits Of The Kuipers

    03/12/2003 5:27:54 PM PST · by RightWhale · 10 replies · 320+ views
    spacedaily.com ^ | 12 Mar 03 | Robert Sanders
    Having Pups Over Pluto And The Planetary Misfits Of The Kuipers Ask any kid how many planets are in our solar system, and you'll get a firm answer: nine. But knock on a few doors in Berkeley's astronomy department, and you'll hear, amid the hemming and hawing, a whole range of numbers. Professor Gibor Basri, who plans soon to propose a formal definition of a planet to the international body that names astronomical objects, argues that there are at least 14 planets, and perhaps as many as 20. To the well-known list of nine he adds several large asteroids and...
  • Astronomers Find a New Planet in Solar System

    07/29/2005 3:35:26 PM PDT · by Right Wing Professor · 114 replies · 6,752+ views
    The New York Times ^ | 7/29/05 | KENNETH CHANG
    Add a 10th planet to the solar system - or possibly subtract one. Astronomers announced today that they have found a lump of rock and ice that is larger than Pluto and the farthest known object in the solar system. The discovery will likely rekindle debate over the definition of "planet" and whether Pluto should still be regarded as one. The new object - as yet unnamed - is currently 9 billion miles away from the Sun, or about three times Pluto's current distance from the Sun. But its 560-year orbit also brings it as close as 3.3 billion miles....
  • 2 Pluto Moons in Need of Devilish Names

    02/12/2013 11:05:53 AM PST · by BenLurkin · 62 replies
    ap ^ | Feb 11, 2013 1:03 PM CST
    Astronomers announced a contest today to name the two itty-bitty moons of Pluto discovered over the past two years. Three Pluto moons already have names associated with Hades and the underworld: Charon, the ferryman of Hades; the half-human, half-fish spirit Nix; and the multi-headed monster Hydra. The two unnamed moons need similarly shady references. Right now, they go by the bland titles of P4 and P5. They're no more than 15 to 20 miles across. Online voting will last two weeks. Twelve choices are available at plutorocks.com,
  • Astronomy Picture of the Day -- Reflected Aurora Over Alaska

    02/12/2013 4:14:48 AM PST · by SunkenCiv · 19 replies
    NASA ^ | February 12, 2013 | (see photo credit)
    Explanation: Some auroras can only be seen with a camera. They are called subvisual and are too faint to be seen with the unaided eye. In the above image, the green aurora were easily visible to the eye, but the red aurora only became apparent after a 20-second camera exposure. The reason is that the human eye only accumulates light for a fraction of a second at a time, while a camera shutter can be left open much longer. When photographing an already picturesque scene near Anchorage, Alaska, USA, last autumn, a camera caught both the visual green and subvisual...
  • Astronomy Picture of the Day -- N11: Star Clouds of the LMC

    02/11/2013 4:53:39 PM PST · by SunkenCiv · 12 replies
    NASA ^ | February 11, 2013 | (see photo credit)
    Explanation: Massive stars, abrasive winds, mountains of dust, and energetic light sculpt one of the largest and most picturesque regions of star formation in the Local Group of Galaxies. Known as N11, the region is visible on the upper right of many images of its home galaxy, the Milky Way neighbor known as the Large Magellanic Clouds (LMC). The above image was taken for scientific purposes by the Hubble Space Telescope and reprocessed for artistry by an amateur to win the Hubble's Hidden Treasures competition. Although the section imaged above is known as NGC 1763, the entire N11 emission nebula...
  • Mystery Mini Moons: How Many Does Earth Have?

    02/10/2013 2:09:02 PM PST · by BenLurkin · 31 replies
    discovery ^ | Feb 7, 2013 11:50 AM ET | // by Irene Klotz
    Earth's gravity may not have the gravitas of Jupiter, but the planet regularly plucks small asteroids passing by and pins them into orbit. The mini-moons don't stay for long. Within a year or so they resume their looping, twisting paths like crazy straws around the sun. But others arrive to take their place. Simulations show that two asteroids the size of dishwashers and a dozen half-meter (1.6 feet) in diameter are orbiting Earth at any given time. Every 50 years or so something the size of a dump truck arrives. So far, there's been just one confirmed sighting. ... A...
  • Astronomy Picture of the Day -- Asteroids in the Distance

    02/09/2013 9:56:44 PM PST · by SunkenCiv · 8 replies
    NASA ^ | February 10, 2013 | (see photo credit)
    Explanation: Rocks from space hit Earth every day. The larger the rock, though, the less often Earth is struck. Many kilograms of space dust pitter to Earth daily. Larger bits appear initially as a bright meteor. Baseball-sized rocks and ice-balls streak through our atmosphere daily, most evaporating quickly to nothing. Significant threats do exist for rocks near 100 meters in diameter, which strike the Earth roughly every 1000 years. An object this size could cause significant tsunamis were it to strike an ocean, potentially devastating even distant shores. A collision with a massive asteroid, over 1 km across, is more...
  • Astronomy Picture of the Day -- The Great Meteor Procession of 1913

    02/09/2013 11:52:18 AM PST · by SunkenCiv · 19 replies
    NASA ^ | February 09, 2013 | (see photo credit)
    Explanation: One hundred years ago today the Great Meteor Procession of 1913 occurred, a sky event described by some as "magnificent" and "entrancing" and which left people feeling "spellbound" and "privileged". Because one had to be in a right location, outside, and under clear skies, only about 1,000 people noted seeing the procession. Lucky sky gazers -- particularly those near Toronto, Canada -- had their eyes drawn to an amazing train of bright meteors streaming across the sky, in groups, over the course of a few minutes. A current leading progenitor hypothesis is that a single large meteor once grazed...
  • Astronomy Picture of the Day -- NGC 6822: Barnard's Galaxy

    02/08/2013 3:57:57 AM PST · by SunkenCiv · 4 replies
    NASA ^ | February 08, 2013 | (see photo credit)
    Explanation: Grand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small galaxies form stars too, like nearby NGC 6822, also known as Barnard's Galaxy. Beyond the rich starfields in the constellation Sagittarius, NGC 6822 is a mere 1.5 million light-years away, a member of our Local Group of galaxies. About 7,000 light-years across, the dwarf irregular galaxy is seen to be filled with young blue stars and mottled with the telltale pinkish hydrogen glow of star forming regions in the deep color composite image. Contributing to...
  • 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...
  • Astronomy Picture of the Day -- Barnard Stares at NGC 2170

    01/19/2013 6:21:02 AM PST · by SunkenCiv · 7 replies
    NASA ^ | January 19, 2013 | (see photo credit)
    Explanation: A gaze across a cosmic skyscape, this telescopic mosaic reveals the continuous beauty of things that are. The evocative scene spans some 6 degrees or 12 Full Moons in planet Earth's sky. At the left, folds of red, glowing gas are a small part of an immense, 300 light-year wide arc. Known as Barnard's loop, the structure is too faint to be seen with the eye, shaped by long gone supernova explosions and the winds from massive stars, and still traced by the light of hydrogen atoms. Barnard's loop lies about 1,500 light-years away roughly centered on the Great...
  • Astronomy Picture of the Day -- Stickney Crater

    01/18/2013 3:13:45 PM PST · by SunkenCiv · 52 replies
    NASA ^ | January 18, 2013 | (see photo credit)
    Explanation: Stickney Crater, the largest crater on the martian moon Phobos, is named for Chloe Angeline Stickney Hall, mathematician and wife of astronomer Asaph Hall. Asaph Hall discovered both the Red Planet's moons in 1877. Over 9 kilometers across, Stickney is nearly half the diameter of Phobos itself, so large that the impact that blasted out the crater likely came close to shattering the tiny moon. This stunning, enhanced-color image of Stickney and surroundings was recorded by the HiRISE camera onboard the Mars Reconnaissance Orbiter as it passed within some six thousand kilometers of Phobos in March of 2008. Even...
  • Astronomy Picture of the Day -- Cas A: Optical and X-ray

    01/17/2013 4:28:40 AM PST · by SunkenCiv · 4 replies
    NASA ^ | January 17, 2013 | (see photo credit)
    Explanation: The aftermath of a cosmic cataclysm, supernova remnant Cassiopeia A (Cas A) is a comfortable 11,000 light-years away. Light from the Cas A supernova, the death explosion of a massive star, first reached Earth just 330 years ago. Still expanding, the explosion's debris cloud spans about 15 light-years near the center of this composite image. The scene combines color data of the starry field and fainter filaments of material at optical energies with image data from the orbiting NuSTAR X-ray telescope. Mapped to false colors, the X-ray data in blue hues trace the fragmented outer ring of the expanding...
  • Comet ISON shaping up to be a spectacular display

    01/16/2013 4:04:36 PM PST · by BenLurkin · 21 replies
    phys.org ^ | January 15, 2013 | by Bob Yirka
    Excitement is mounting for astronomers and star gazers the world over as word spreads that Comet ISON may go down in the history books as one of the flashiest ever. First discovered in September of last year by Russian astronomers, Vitali Nevski and Artyom Novichonok, Comet ISON (C/2012 S1) has been drawing attention ever since. Of course, projecting the brilliance of a comet or its tail length is an iffy proposition to be sure. It could just break apart when it nears the sun (it's expected to come as close as 32,000 miles), leaving us here on Earth less than...
  • Astronomy Picture of the Day -- NGC 1309: Spiral Galaxy and Friends

    01/16/2013 4:03:13 PM PST · by SunkenCiv · 6 replies
    NASA ^ | January 16, 2013 | (see photo credit)
    Explanation: A gorgeous spiral galaxy some 100 million light-years distant, NGC 1309 lies on the banks of the constellation of the River (Eridanus). NGC 1309 spans about 30,000 light-years, making it about one third the size of our larger Milky Way galaxy. Bluish clusters of young stars and dust lanes are seen to trace out NGC 1309's spiral arms as they wind around an older yellowish star population at its core. Not just another pretty face-on spiral galaxy, observations of NGC 1309's recent supernova and Cepheid variable stars contribute to the calibration of the expansion of the Universe. Still, after...
  • Astronomy Picture of the Day -- A Solar Ballet

    01/15/2013 4:05:56 AM PST · by SunkenCiv · 8 replies
    NASA ^ | January 15, 2012 | (see photo credit)
    Explanation: Sometimes, the Sun itself seems to dance. On just this past New Year's Eve, for example, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressive prominence erupting from the Sun's surface. The dramatic explosion was captured in ultraviolet light in the above time lapse video covering four hours. Of particular interest is the tangled magnetic field that directs a type of solar ballet for the hot plasma as it falls back to the Sun. The scale of the disintegrating prominence is huge -- the entire Earth would easily fit under the flowing curtain of hot gas. A quiescent prominence...
  • Astronomy Picture of the Day -- NGC 2170: Celestial Still Life

    01/14/2013 6:57:55 PM PST · by SunkenCiv · 17 replies
    NASA ^ | January 14, 2012 | (see photo credit)
    Explanation: In this celestial still life composed with a cosmic brush, dusty nebula NGC 2170 shines left of image center. Reflecting the light of nearby hot stars, NGC 2170 is joined by other bluish reflection nebulae, a red emission region, many dark absorption nebulae, and a backdrop of colorful stars. Like the common household items still life painters often choose for their subjects, these clouds of gas, dust, and hot stars are also commonly found in this setting -- a massive, star-forming molecular cloud in the constellation Monoceros. The giant molecular cloud, Mon R2, is impressively close, estimated to be...
  • Astronomy Picture of the Day -- NGC 602 and Beyond

    01/13/2013 8:47:25 AM PST · by SunkenCiv · 12 replies
    NASA ^ | January 13, 2012 | (see photo credit)
    Explanation: Near the outskirts of the Small Magellanic Cloud, a satellite galaxy some 200 thousand light-years distant, lies 5 million year young star cluster NGC 602. Surrounded by natal gas and dust, NGC 602 is featured in this stunning Hubble image of the region. Fantastic ridges and swept back shapes strongly suggest that energetic radiation and shock waves from NGC 602's massive young stars have eroded the dusty material and triggered a progression of star formation moving away from the cluster's center. At the estimated distance of the Small Magellanic Cloud, the picture spans about 200 light-years, but a tantalizing...
  • Astronomy Picture of the Day -- Ten Billion Earths

    01/11/2013 9:37:59 PM PST · by SunkenCiv · 9 replies
    NASA ^ | January 12, 2012 | (see photo credit)
    Explanation: How common are Earth-sized planets? Quite common, according to extrapolations from new data taken by NASA's orbiting Kepler spacecraft. Current computer models are indicating that at least one in ten stars are orbited by an Earth-sized planet, making our Milky Way Galaxy the home to over ten billion Earths. Unfortunately, this estimate applies only to planets effectively inside the orbit of Mercury, making these hot-Earths poor vacation opportunities for humans. This histogram depicts the estimated fraction of stars that have close orbiting planets of various sizes. The number of Sun-like stars with Earth-like planets in Earth-like orbits is surely...
  • Astronomy Picture of the Day -- The Fornax Cluster of Galaxies

    01/11/2013 3:10:10 AM PST · by SunkenCiv · 9 replies
    NASA ^ | January 11, 2012 | (see photo credit)
    Explanation: How do clusters of galaxies form and evolve? To help find out, astronomers continue to study the second closest cluster of galaxies to Earth: the Fornax cluster, named for the southern constellation toward which most of its galaxies can be found. Although almost 20 times more distant than our neighboring Andromeda galaxy, Fornax is only about 10 percent further that the better known and more populated Virgo cluster of galaxies. Fornax has a well-defined central region that contains many galaxies, but is still evolving. It has other galaxy groupings that appear distinct and have yet to merge. Seen here,...
  • Astronomy Picture of the Day -- The Orion Bullets

    01/10/2013 3:45:10 AM PST · by SunkenCiv · 10 replies
    NASA ^ | January 10, 2012 | (see photo credit)
    Explanation: Cosmic bullets pierce the outskirts of the Orion Nebula some 1500 light-years distant in this sharp infrared close-up. Blasted out by energetic massive star formation the bullets, relatively dense, hot gas clouds about ten times the size of Pluto's orbit, are blue in the false color image. Glowing with the light of ionized iron atoms they travel at speeds of hundreds of kilometers per second, their passage traced by yellowish trails of the nebula's shock-heated hydrogen gas. The cone-shaped wakes are up to a fifth of a light-year long. The detailed image was created using the 8.1 meter Gemini...
  • Astronomy Picture of the Day -- The Elusive Jellyfish Nebula

    01/09/2013 4:51:54 PM PST · by SunkenCiv · 9 replies
    NASA ^ | January 09, 2012 | (see photo credit)
    Explanation: Normally faint and elusive, the Jellyfish Nebula is caught in this alluring telescopic view. Drifting near bright star Eta Geminorum, at the foot of a celestial twin, the Jellyfish Nebula is seen dangling tentacles from the bright arcing ridge of emission left of center. In fact, the cosmic jellyfish is part of bubble-shaped supernova remnant IC 443, the expanding debris cloud from a massive star that exploded. Light from the explosion first reached planet Earth over 30,000 years ago. Like its cousin in astrophysical waters the Crab Nebula supernova remnant, IC 443 is known to harbor a neutron star,...
  • Astronomy Picture of the Day -- Grand Spiral Galaxy NGC 7424

    01/08/2013 6:47:16 PM PST · by SunkenCiv · 10 replies
    NASA ^ | January 08, 2012 | (see photo credit)
    Explanation: The grand, winding arms are almost mesmerizing in this face-on view of NGC 7424, a spiral galaxy with a prominent central bar. About 40 million light-years distant in the headlong constellation Grus, this island universe is also about 100,000 light-years across making it remarkably similar to our own Milky Way. Following along the winding arms, many bright clusters of massive young stars can be found. The star clusters themselves are several hundred light-years in diameter. And while massive stars are born in the arms of NGC 7424, they also die there. Notably, this galaxy was home to a powerful...
  • Astronomy Picture of the Day -- AE Aurigae and the Flaming Star Nebula

    01/07/2013 4:52:59 PM PST · by SunkenCiv · 8 replies
    NASA ^ | January 07, 2012 | (see photo credit)
    Explanation: AE Aurigae is called the flaming star. The surrounding nebula IC 405 is named the Flaming Star Nebula and the region seems to harbor smoke, but there is no fire. Fire, typically defined as the rapid molecular acquisition of oxygen, happens only when sufficient oxygen is present and is not important in such high-energy, low-oxygen environments. The material that appears as smoke is mostly interstellar hydrogen, but does contain smoke-like dark filaments of carbon-rich dust grains. The bright star AE Aurigae, visible near the nebula center, is so hot it is blue, emitting light so energetic it knocks electrons...
  • Astronomy Picture of the Day -- The Dark Tower in Scorpius

    01/05/2013 9:26:50 PM PST · by SunkenCiv · 21 replies
    NASA ^ | January 06, 2012 | (see photo credit)
    Explanation: In silhouette against a crowded star field toward the constellation Scorpius, this dusty cosmic cloud evokes for some the image of an ominous dark tower. In fact, clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across this gorgeous telescopic portrait. Known as a cometary globule, the swept-back cloud, extending from the lower right to the head (top of the tower) left and above center, is shaped by intense ultraviolet radiation from the OB association of very hot stars in NGC 6231, off the...