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Astronomy (General/Chat)

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  • NASA Says A Thigh Bone Was Not Found on Mars

    08/25/2014 4:24:46 PM PDT · by CivilWarBrewing · 52 replies
    Weather.com ^ | August 24, 2014 | Laura Dattaro
    An image from the Curiosity rover that some people thought showed a “thigh bone” on Mars is just a photo of a weathered rock, according to NASA. The photo shows the dirt-covered surface of Mars littered with bits of rock, one of which is elongated in a shape similar to a leg bone. The image was first picked up on a UFO blog, Space.com reports, purporting to show evidence of past alien life on the planet. The claim got so much attention that NASA released the photo with an official explanation — saying the object did look like a thigh...
  • Astronomy Picture of the Day -- Arp 188 and the Tadpole's Tail

    08/24/2014 9:23:44 PM PDT · by SunkenCiv · 11 replies
    NASA ^ | August 25, 2014 | (see photo credit)
    Explanation: Why does this galaxy have such a long tail? In this stunning vista, based on image data from the Hubble Legacy Archive, distant galaxies form a dramatic backdrop for disrupted spiral galaxy Arp 188, the Tadpole Galaxy. The cosmic tadpole is a mere 420 million light-years distant toward the northern constellation Draco. Its eye-catching tail is about 280 thousand light-years long and features massive, bright blue star clusters. One story goes that a more compact intruder galaxy crossed in front of Arp 188 - from right to left in this view - and was slung around behind the Tadpole...
  • Astronomy Picture of the Day -- Mercury's Transit: An Unusual Spot on the Sun

    08/24/2014 1:39:14 PM PDT · by SunkenCiv · 6 replies
    NASA ^ | August 24, 2014 | (see photo credit)
    Explanation: What's that dot on the Sun? If you look closely, it is almost perfectly round. The dot is the result of an unusual type of solar eclipse that occurred in 2006. Usually it is the Earth's Moon that eclipses the Sun. This time, the planet Mercury took a turn. Like the approach to New Moon before a solar eclipse, the phase of Mercury became a continually thinner crescent as the planet progressed toward an alignment with the Sun. Eventually the phase of Mercury dropped to zero and the dark spot of Mercury crossed our parent star. The situation could...
  • Astronomy Picture of the Day -- The Spectre of Veszprem

    08/23/2014 8:24:37 PM PDT · by SunkenCiv · 2 replies
    NASA ^ | August 23, 2014 | (see photo credit)
    Explanation: The city of Veszprem, Hungary was only briefly haunted by this mysterious spectre. On the morning of August 11, its monstrous form hovered in the mist above municipal buildings near the town center. A clue to its true identity is offered by the photographer, though, who reports he took the picture from the top of a twenty story building with the rising Sun directly at his back. That special geometry suggests this is an example of an atmospheric phenomenon called the Glory or sometimes "the Spectre of the Brocken". Also seen from mountain tops and airplanes when looking opposite...
  • Astronomy Picture of the Day -- Comet Jacques, Heart and Soul

    08/23/2014 8:13:44 PM PDT · by SunkenCiv · 7 replies
    NASA ^ | August 22, 2014 | (see photo credit)
    Explanation: On July 13th, a good place to watch Comet Jacques was from Venus. Then, the recently discovered visitor (C/2014 E2) to the inner solar system passed within about 14.5 million kilometers of our sister planet. But the outbound comet will pass only 84 million kilometers from our fair planet on August 28 and is already a fine target for telescopes and binoculars. Two days ago Jacques' greenish coma and straight and narrow ion tail were captured in this telescopic snapshot, a single 2 minute long exposure with a modified digital camera. The comet is flanked by IC 1805 and...
  • Astronomy Picture of the Day -- Venus and Jupiter at Dawn

    08/23/2014 8:06:08 PM PDT · by SunkenCiv · 4 replies
    NASA ^ | August 21, 2014 | (see photo credit)
    Explanation: On Monday morning, Venus and Jupiter gathered close in dawn skies, for some separated by about half the width of a full moon. It was their closest conjunction since 2000, captured here above the eastern horizon before sunrise. The serene and colorful view is from Istia beach near the city of Capoliveri on the island of Elba. Distant lights and rolling hills are along Italy's Tuscan coast. Of course, the celestial pair soon wandered apart. Brighter Venus headed lower, toward the eastern horizon and the glare of the Sun, while Jupiter continues to rise a little higher now in...
  • Astronomy Picture of the Day -- In the Center of the Lagoon Nebula

    08/23/2014 8:02:31 PM PDT · by SunkenCiv · 1 replies
    NASA ^ | August 20, 2014 | (see photo credit)
    Explanation: The center of the Lagoon Nebula is a whirlwind of spectacular star formation. Visible near the image center, at least two long funnel-shaped clouds, each roughly half a light-year long, have been formed by extreme stellar winds and intense energetic starlight. The tremendously bright nearby star, Herschel 36, lights the area. Walls of dust hide and redden other hot young stars. As energy from these stars pours into the cool dust and gas, large temperature differences in adjoining regions can be created generating shearing winds which may cause the funnels. This picture, spanning about 5 light years, combines images...
  • Astronomy Picture of the Day -- Contrasting Terrains on Comet Churyumov-Gerasimenko

    08/23/2014 7:58:55 PM PDT · by SunkenCiv · 21 replies
    NASA ^ | August 19, 2014 | (see photo credit)
    Explanation: Where should Philae land? As ESA's robotic spacecraft Rosetta circles toward Comet 67P/ Churyumov-Gerasimenko, a decision must eventually be made as to where its mechanical lander should attempt to touch-down. Reaching the comet earlier this month, Rosetta is sending back detailed pictures of the comet's unusual nucleus from which a smooth landing site will be selected. Pictured above, near the image top, the head of the comet's nucleus shows rugged grooves, while near the image bottom, the body shows a patch-work of areas sometimes separated by jagged hills. Some of the patch-work areas apparent on both the head and...
  • Galileo satellites go into wrong, lower orbit

    08/23/2014 1:31:44 PM PDT · by DUMBGRUNT · 29 replies
    BBC ^ | 23 August 2014
    The European Space Agency (Esa) says the latest two satellites for Europe's version of the American GPS satellite navigation system have not gone into the correct orbit.
  • Huge Asteroid Heading for Earth... Possible Impact March 16, 2880

    08/22/2014 2:31:59 PM PDT · by nickcarraway · 80 replies
    Emirates 24/7 ^ | Friday, August 22, 2014
    However, scientists claim there is no cause for concern because the hundreds of years of warning could allow for a method to divert itResearchers studying a huge asteroid that is hurtling towards earth say there is a possibility of it striking our planet on March 16, 2880! They say the rock rotates so quickly that it should break apart, but it remained intact on its Earth-bound trajectory, according to a report in Dailymail.co.uk Though studies have revealed that Asteroid 1950DA is held together by cohesive forces called van der Waals, scientists still have no clue on how to stop it....
  • SECCHI Image (What is that?)

    08/21/2014 4:55:50 PM PDT · by Talisker · 25 replies
    SECCHI ^ | US Navy/NASA
    Amazing photo from SECCHI HI2 dated August 18, 2014. What the heck is that thing?! The big dot on the right with the line going through it is the planet Venus.
  • Astronomy Picture of the Day -- Star Trails Over Indonesia

    08/18/2014 7:00:19 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 18, 2014 | (see photo credit)
    Explanation: Both land and sky were restless. The unsettled land included erupting Mount Semeru in the distance, the caldera of steaming Mount Bromo on the left, flowing fog, and the lights of moving cars along roads that thread between hills and volcanoes in Bromo Tengger Semeru National Park in East Java, Indonesia. The stirring sky included stars circling the South Celestial Pole and a meteor streaking across the image right. The above 270-image composite was taken from King Kong Hill in mid-June over two hours, with a rising Moon lighting the landscape.
  • Astronomy Picture of the Day -- Jupiter and Venus from Earth

    08/17/2014 6:27:19 AM PDT · by SunkenCiv · 34 replies
    NASA ^ | August 17, 2014 | (see photo credit)
    Explanation: It was visible around the world. The sunset conjunction of Jupiter and Venus in 2012 was visible almost no matter where you lived on Earth. Anyone on the planet with a clear western horizon at sunset could see them. Pictured above in 2012, a creative photographer traveled away from the town lights of Szubin, Poland to image a near closest approach of the two planets. The bright planets were separated only by three degrees and his daughter striking a humorous pose. A faint red sunset still glowed in the background. Early tomorrow (Monday) morning, the two planets will pass...
  • Public gets to nominate and vote on exoplanet names

    08/16/2014 10:56:11 AM PDT · by null and void · 15 replies
    Electronic Products ^ | 07/14/2014 | Max Teodorescu
    Sorry, no pop-culture references Astronomers have amassed such a gigantic database of identifiable celestial bodies, that naming these objects has largely fallen wayside in favor of efficiency. Devoting time and creative energy cooking up a unique name for a dot in the sky is not worth NASA’s (or other space agencies) time, considering the millions of stars in the observable universe. Exoplanets, planets orbiting a star other than our own, are a different story. Our spacecrafts and telescopes have only spotted about 1800 of them, including the first potentially habitable Earth-sized planet, a planet anticlimactically named Kepler-186F. This is all...
  • Astronomy Picture of the Day -- No X-rays from SN 2014J

    08/16/2014 4:53:24 AM PDT · by SunkenCiv · 8 replies
    NASA ^ | August 16, 2014 | (see photo credit)
    Explanation: Last January, telescopes in observatories around planet Earth were eagerly used to watch the rise of SN 2014J, a bright supernova in nearby galaxy M82. Still, the most important observations may have been from orbit where the Chandra X-ray Observatory saw nothing. Identified as a Type Ia supernova, the explosion of SN2014J was thought to be triggered by the buildup of mass on a white dwarf star steadily accreting material from a companion star. That model predicts X-rays would be generated when the supernova blastwave struck the material left surrounding the white dwarf. But no X-rays were seen from...
  • Astronomy Picture of the Day -- A Luminous Night

    08/15/2014 6:54:51 PM PDT · by SunkenCiv · 9 replies
    NASA ^ | August 15, 2014 | (see photo credit)
    Explanation: What shines in the world at night? Just visible to the eye, a rare electric blue glow spread along the shores of Victoria Lake on January 16, 2013. Against reflections of a light near the horizon, this digitally stacked long exposure recorded the bioluminescence of Noctiluca scintillans, plankton stimulated by the lapping waves. Above, the night skies of the Gippsland Lakes region, Victoria, Australia shine with a fainter greenish airglow. Oxygen atoms in the upper atmosphere, initially excited by ultraviolet sunlight, produce the more widely seen fading atmospheric chemiluminescence. Washed out by the Earth's rotation, the faint band of...
  • Astronomy Picture of the Day -- Surreal Moon

    08/14/2014 8:11:00 PM PDT · by SunkenCiv · 15 replies
    NASA ^ | August 14, 2014 | (see photo credit)
    Explanation: Big, bright, and beautiful, a Full Moon near perigee, the closest point in its elliptical orbit around our fair planet, rose on August 10. This remarkable picture records the scene with a dreamlike quality from the east coast of the United States. The picture is actually a composite of 10 digital frames made with exposures from 1/500th second to 1 second long, preserving contrast and detail over a much wider than normal range of brightness. At a perigee distance of a mere 356,896 kilometers, August's Full Moon was the closest, and so the largest and most super, of the...
  • Astronomy Picture of the Day -- Rings Around the Ring Nebula

    08/14/2014 8:08:39 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 13, 2014 | (see photo credit)
    Explanation: It is a familiar sight to sky enthusiasts with even a small telescope. There is much more to the Ring Nebula (M57), however, than can be seen through a small telescope. The easily visible central ring is about one light-year across, but this remarkably deep exposure - a collaborative effort combining data from three different large telescopes - explores the looping filaments of glowing gas extending much farther from the nebula's central star. This remarkable composite image includes narrowband hydrogen image, visible light emission, and infrared light emission. Of course, in this well-studied example of a planetary nebula, the...
  • NASA’S NuSTAR Catches a Black Hole Bending Light, Space, and Time

    08/13/2014 2:46:34 PM PDT · by BenLurkin · 17 replies
    universetoday.com ^ | August 13, 2014 | Shannon Hall on
    In just a matter of days, the corona — a cloud of particles traveling near the speed of light — fell in toward the black hole. The observations are a powerful test of Einstein’s theory of general relativity, which says gravity can bend space-time, the fabric that shapes our universe, and the light that travels through it. “The corona recently collapsed in toward the black hole, with the result that the black hole’s intense gravity pulled all the light down onto its surrounding disk, where material is spiraling inward,” said coauthor Michael Parker from the Institute of Astronomy ... NuSTAR...
  • A Spectacular Dawn Conjunction of Venus and Jupiter Set For August 18th

    08/13/2014 2:39:16 PM PDT · by BenLurkin · 3 replies
    universetoday.com ^ | August 13, 2014 | David Dickinson on
    We’re talking about a conjunction of the planets Jupiter and Venus. Venus has been dominating the dawn sky for 2014, and Jupiter is fresh off of solar conjunction on the far side of the Sun on July 24th and is currently racing up to greet it. We just caught sight of Jupiter for the first time for this apparition yesterday from our campsite on F.E. Warren Air Force Base in Cheyenne, Wyoming. We’d just wrapped up an early vigil for Perseid meteors and scrambled to shoot a quick sequence of the supermoon setting behind a distant wind farm. Jupiter was...
  • Rosetta’s Comet Already Spewing Dust, One Year Before Getting Close To The Sun

    08/13/2014 6:49:26 AM PDT · by BenLurkin · 7 replies
    universetoday.com ^ | August 13, 2014 | Elizabeth Howell on
    Preliminary measurements by a dust detector aboard the Rosetta spacecraft show that dust is at least as frequent — or perhaps even more abundant — than what models have predicted. Meanwhile, as reported on Universe Today earlier this week, Rosetta’s COSIMA instrument is also doing dust measurements. Rosetta’s Grain Impact Analyser and Dust Accumulator (GIADA) has already detected four dust grains on its impact sensor. The detections took place between Aug. 1 and Aug. 5 at various distances as Rosetta approached the comet, starting from as far as 814 kilometers (506 miles) to as close as 179 kilometers (111 miles)....
  • Astronomy Picture of the Day -- Collapse in Hebes Chasma on Mars

    08/11/2014 11:20:40 PM PDT · by SunkenCiv · 19 replies
    NASA ^ | August 12, 2014 | (see photo credit)
    Explanation: What's happened in Hebes Chasma on Mars? Hebes Chasma is a depression just north of the enormous Valles Marineris canyon. Since the depression is unconnected to other surface features, it is unclear where the internal material went. Inside Hebes Chasma is Hebes Mensa, a 5 kilometer high mesa that appears to have undergone an unusual partial collapse -- a collapse that might be providing clues. The above image, taken by the robotic Mars Express spacecraft currently orbiting Mars, shows great details of the chasm and the unusual horseshoe shaped indentation in the central mesa. Material from the mesa appears...
  • Astronomy Picture of the Day -- Rosetta Approaches Comet Churyumov-Gerasimenko

    08/11/2014 7:28:57 PM PDT · by SunkenCiv · 6 replies
    NASA ^ | August 11, 2014 | (see photo credit)
    Explanation: What does it look like to approach a comet? Early this month humanity received a new rendition as the robotic Rosetta spacecraft went right up to -- and began orbiting -- the nucleus of Comet 67P/Churyumov-Gerasimenko. This approach turned out to be particularly fascinating because the comet nucleus first revealed itself to have an unexpected double structure, and later showed off an unusual and craggily surface. The above 101-frame time-lapse video details the approach of the spacecraft from August 1 through August 6. The icy comet's core is the size of a mountain and rotates every 12.7 hours. Rosetta's...
  • Supermoon rises at sunset; earth, moon get intimate

    08/10/2014 5:51:51 PM PDT · by BenLurkin · 15 replies
    stgeorgeutah.com ^ | August 10, 2014 | Aspen Stoddard
    After reaching its fullest stage at 2:09 p.m., this summer’s most super “supermoon” will begin to peek up over the eastern horizon at approximately 8:24 p.m. Sunday delivering a true celestial treat for moon lovers and stargazers alike. ... As long as the sky is clear, the moon should appear 14 percent bigger and 30 percent brighter tonight. In reality, the enhanced size and luminosity of a supermoon, especially when it hangs closest to the horizon, is but an unexplainable illusion in the scientific realm.
  • Astronomy Picture of the Day -- A Perseid Below

    08/09/2014 10:33:02 PM PDT · by SunkenCiv · 4 replies
    NASA ^ | August 10, 2014 | (see photo credit)
    Explanation: Denizens of planet Earth typically watch meteor showers by looking up. But this remarkable view, captured on August 13, 2011 by astronaut Ron Garan, caught a Perseid meteor by looking down. From Garan's perspective onboard the International Space Station orbiting at an altitude of about 380 kilometers, the Perseid meteors streak below, swept up dust left from comet Swift-Tuttle heated to incandescence. The glowing comet dust grains are traveling at about 60 kilometers per second through the denser atmosphere around 100 kilometers above Earth's surface. In this case, the foreshortened meteor flash is right of frame center, below the...
  • Astronomy Picture of the Day -- A Luminous Night

    08/09/2014 2:38:00 PM PDT · by SunkenCiv · 6 replies
    NASA ^ | August 09, 2014 | (see photo credit)
    Explanation: What shines in the world at night? Just visible to the eye, a rare electric blue glow spread along the shores of Victoria Lake on January 16, 2013. Against reflections of a light near the horizon, this digitally stacked long exposure recorded the bioluminescence of noctiluca scintillans, plankton stimulated by the lapping waves. Above, the night skies of the Gippsland Lakes region, Victoria, Australia shine with a fainter greenish airglow. Oxygen atoms in the upper atmosphere, initially excited by ultraviolet sunlight, produce the more widely seen fading atmospheric chemiluminescence. Washed out by the Earth's rotation, the faint band of...
  • Astronomy Picture of the Day -- Spiral Galaxy NGC 6744

    08/09/2014 2:35:15 PM PDT · by SunkenCiv · 2 replies
    NASA ^ | August 08, 2014 | (see photo credit)
    Explanation: Big, beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across, larger than our own Milky Way. It lies some 30 million light-years distant in the southern constellation Pavo. We see the disk of the nearby island universe tilted towards our line of sight. Orientation and composition give a strong sense of depth to this colorful galaxy portrait that covers an area about the angular size of the full moon. This giant galaxy's yellowish core is dominated by the light from old, cool stars. Beyond the core, spiral arms filled with young blue star clusters and pinkish star forming...
  • Astronomy Picture of the Day -- Rosetta's Rendezvous

    08/09/2014 2:32:21 PM PDT · by SunkenCiv · 6 replies
    NASA ^ | August 07, 2014 | (see photo credit)
    Explanation: On August 3rd, the Rosetta spacecraft's narrow angle camera captured this stunning image of the nucleus of Comet 67P/Churyumov-Gerasimenko. After 10 years and 6.5 billion kilometers of travel along gravity assist trajectories looping through interplanetary space, Rosetta had approached to within 285 kilometers of its target. The curious double-lobed shape of the nucleus is revealed in amazing detail at an image resolution of 5.3 meters per pixel. About 4 kilometers across, the comet nucleus is presently just over 400 million kilometers from Earth, between the orbits of Jupiter and Mars. Now the first spacecraft to achieve a delicate orbit...
  • Astronomy Picture of the Day -- Saturn's Swirling Cloudscape

    08/09/2014 2:29:27 PM PDT · by SunkenCiv · 6 replies
    NASA ^ | August 06, 2014 | (see photo credit)
    Explanation: Acquiring its first sunlit views of far northern Saturn in late 2012, the Cassini spacecraft's wide-angle camera recorded this stunning, false-color image of the ringed planet's north pole. The composite of near-infrared image data results in red hues for low clouds and green for high ones, giving the Saturnian cloudscape a vivid appearance. Enormous by terrestrial standards, Saturn's north polar hurricane-like storm is deep, red, and about 2,000 kilometers wide. Clouds at its outer edge travel at over 500 kilometers per hour. Other atmospheric vortices also swirl inside the large, yellowish green, six-sided jet stream known as the hexagon....
  • Astronomy Picture of the Day -- Four Billion BCE: Battered Earth

    08/09/2014 2:26:38 PM PDT · by SunkenCiv · 20 replies
    NASA ^ | August 05, 2014 | (see photo credit)
    Explanation: No place on Earth was safe. Four billion years ago, during the Hadean eon, our Solar System was a dangerous shooting gallery of large and dangerous rocks and ice chunks. Recent examination of lunar and Earth bombardment data indicate that the entire surface of the Earth underwent piecemeal upheavals, hiding our globe's ancient geologic history, and creating a battered world with no remaining familiar land masses. The rain of devastation made it difficult for any life to survive, although bacteria that could endure high temperatures had the best chance. Oceans thought to have formed during this epoch would boil...
  • Astronomy Picture of the Day -- Shadows and Plumes Across Enceladus

    08/08/2014 4:40:10 PM PDT · by SunkenCiv · 9 replies
    NASA ^ | August 04, 2014 | (see photo credit)
    Explanation: Why does Enceladus have ice plumes? The discovery of jets spewing water vapor and ice was detected by the Saturn-orbiting Cassini spacecraft in 2005. The origin of the water feeding the jets, however, remained a topic of research. A leading hypothesis held that the source might originate from a deep underground sea, but another hypothesis indicated that it might just be ice melted off walls of deep rifts by the moon's tidal flexing and heating. Pictured above, the textured surface of Enceladus is visible in the foreground, while rows of plumes rise from ice fractures in the distance. These...
  • Watch Pluto and Charon Engage in Their Orbital Dance

    08/08/2014 12:27:44 PM PDT · by BenLurkin · 19 replies
    universetoday.com ^ | August 7, 2014 | Jason Major
    Now here’s something I guarantee you’ve never seen before: a video of the dwarf planet Pluto and its largest moon Charon showing the two distinctly separate worlds actually in motion around each other! Captured by the steadily-approaching New Horizons spacecraft from July 19–24, the 12 images that comprise this animation were acquired with the Long Range Reconnaissance Imager (LORRI) instrument from distances of 267 million to 262 million miles (429 million to 422 million km) and show nearly a full orbital rotation. ... Pluto and Charon are seen circling a central gravitational point known as the barycenter, which accounts for...
  • Rosetta's crazy insertion maneuvers to get into orbit about comet 67P (animation)

    08/08/2014 11:46:03 AM PDT · by LibWhacker · 26 replies
  • Weak supernova might have left zombie star

    08/07/2014 10:32:03 AM PDT · by ConservingFreedom · 13 replies
    EarthSky ^ | Aug 07, 2014 | Science Wire, Space
    Astronomers are scrutinizing a star system in a distant galaxy that exploded, possibly leaving behind a zombie star. They say their study of this system will help them understand supernova explosions, which are an important piece of the cosmic puzzle, used to help measure distances in vast space and the expansion of the universe. Standard Type Ia supernovae occur when a white dwarf draws enough material from a companion star onto itself to raise its own core temperature, ultimately creating a runaway nuclear reaction that causes the white dwarf to explode as a supernova. In such cases, the explosion typically...
  • The ‘Force’ of George Lucas is everywhere at Skywalker Ranch

    08/06/2014 11:18:46 PM PDT · by nickcarraway · 6 replies
    Gulf News ^ | August 6, 2014
    George Lucas, the man behind the mega-successful interplanetary saga Star Wars, may well have retired, but his spirit looms large at the famous Skywalker Ranch. The creator of Luke, Leia, Indiana Jones and Darth Vader bought the property in 1978 with proceeds from his first blockbuster hit, Star Wars to realise his dream of creating a haven for filmmaking outside Hollywood, at a cost of around $100 million (Dh367 million), according to the Wall Street Journal. Rare visitors allowed into the huge complex — 1,900 hectares near San Francisco — must first weave around hills, orchards, and pastures occupied by...
  • Rosetta on Final Approach to Historic Comet Rendezvous – Watch Live Here

    08/05/2014 9:41:44 PM PDT · by BenLurkin · 14 replies
    universetoday.com ^ | August 5, 2014 | Ken Kremer on
    After a decade long chase of 6.4 billion kilometers (4 Billion miles) through interplanetary space the European Space Agency’s (ESA) Rosetta spacecraft is now on final approach for its historic rendezvous with its target comet 67P scheduled for Wednesday morning, Aug. 6. some half a billion kilometers from the Sun. See online webcast below. Rosetta arrives at Comet 67P/Churyumov-Gerasimenko in less than 12 hours and is currently less than 200 kilometers away.
  • Getting to Know Comet 67P/Churyumov-Gerasimenko

    08/03/2014 10:17:36 AM PDT · by BenLurkin · 8 replies
    universetoday.com ^ | August 3, 2014 | Bob King
    For all the wonder that comets evoke, we on Earth never see directly what whips up the coma and tail. Even professional telescopes can’t burrow through the dust and vapor cloaking the nucleus to distinguish the clear outline of a comet’s heart. The only way to see one is to fly a camera there. Rosetta took 10 years to reach 67P/C-G, a craggy, boot-shaped body that resembles an asteroid in appearance but with key differences. Asteroids shown in close up photos often display typical bowl-shaped impact craters. From the photos to date, 67P/C-G’s ‘craters’ look shallow and flat in comparison...
  • Astronomy Picture of the Day -- Dark Shuttle Approaching

    08/03/2014 9:08:12 AM PDT · by SunkenCiv · 12 replies
    NASA ^ | August 03, 2014 | (see photo credit)
    Explanation: What's that approaching? Astronauts on board the International Space Station first saw it in early 2010 far in the distance. Soon it enlarged to become a dark silhouette. As it came even closer, the silhouette appeared to be a spaceship. Finally, the object revealed itself to be the Space Shuttle Endeavour, and it soon docked as expected with the Earth-orbiting space station. Pictured above, Endeavour was imaged near Earth's horizon as it approached, where several layers of the Earth's atmosphere were visible. Directly behind the shuttle is the mesosphere, which appears blue. The atmospheric layer that appears white is...
  • Astronomy Picture of the Day -- NGC 7023: The Iris Nebula

    08/01/2014 10:40:14 PM PDT · by SunkenCiv · 7 replies
    NASA ^ | August 02, 2014 | (see photo credit)
    Explanation: These clouds of interstellar dust and gas have blossomed 1,300 light-years away in the fertile star fields of the constellation Cepheus. Sometimes called the Iris Nebula, NGC 7023 is not the only nebula in the sky to evoke the imagery of flowers, though. Still, this deep telescopic view shows off the Iris Nebula's range of colors and symmetries in impressive detail. Within the Iris, dusty nebular material surrounds a hot, young star. The dominant color of the brighter reflection nebula is blue, characteristic of dust grains reflecting starlight. Central filaments of the dusty clouds glow with a faint reddish...
  • Astronomy Picture of the Day -- Tetons and Snake River, Planet Earth

    07/31/2014 10:57:05 PM PDT · by SunkenCiv · 11 replies
    NASA ^ | August 01, 2014 | (see photo credit)
    Explanation: An alluring night skyscape, this scene looks west across the Grand Teton National Park, Wyoming, USA, Planet Earth. The Snake River glides through the foreground, while above the Tetons' rugged mountain peaks the starry sky is laced with exceptionally strong red and green airglow. That night, the luminous atmospheric glow was just faintly visible to the eye, its color and wavey structure captured only by a sensitive digital camera. In fact, this contemporary digital photograph matches the location and perspective of a well-known photograph from 1942 - The Tetons and The Snake River , by Ansel Adams, renown photographer...
  • Astronomy Picture of the Day -- Veins of Heaven

    07/31/2014 10:53:41 PM PDT · by SunkenCiv · 4 replies
    NASA ^ | July 31, 2014 | (see photo credit)
    Explanation: Transfusing sunlight through a still dark sky, this exceptional display of noctilucent clouds was captured earlier this month above the island of Gotland, Sweden. From the edge of space, about 80 kilometers above Earth's surface, the icy clouds reflect sunlight even though the Sun itself is below the horizon as seen from the ground. Usually spotted at high latitudes in summer months the night shining clouds made a strong showing this July. Also known as polar mesopheric clouds they are understood to form as water vapor driven into the cold upper atmosphere condenses on the fine dust particles supplied...
  • Astronomy Picture of the Day -- M31: The Andromeda Galaxy

    07/31/2014 10:49:52 PM PDT · by SunkenCiv · 7 replies
    NASA ^ | July 30, 2014 | (see photo credit)
    Explanation: Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about two...
  • Astronomy Picture of the Day -- A Sky Portal in New Zealand

    07/31/2014 10:44:57 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | July 29, 2014 | (see photo credit)
    Explanation: To some, it may look like a portal into the distant universe. To others, it may appear as the eye of a giant. Given poetic license, both are correct. Pictured above is a standard fisheye view of the sky -- but with an unusual projection. The view is from a perch in New Zealand called Te Mata Peak, a name that translates from the Maori language as "Sleeping Giant". The wondrous panorama shows the band of our Milky Way Galaxy right down the center of the sky, with the Large and Small Magellanic Clouds visible to the right. The...
  • Astronomy Picture of the Day -- The Horsehead Nebula from Blue to Infrared

    07/31/2014 10:39:56 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | July 28, 2014 | (see photo credit)
    Explanation: One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. Also known as Barnard 33, the unusual shape was first discovered on a photographic plate in the late 1800s. The red glow originates from hydrogen gas predominantly behind the nebula, ionized by the nearby bright star Sigma Orionis. The darkness of the Horsehead is caused mostly by thick dust, although the lower part of the Horsehead's neck casts a shadow to the left. Streams of gas leaving the nebula are funneled by a strong magnetic field. Bright...
  • What Is The Speed of Dark? (video only)

    07/29/2014 3:55:02 PM PDT · by servo1969 · 7 replies
    YouTube.com ^ | 7-29-2014 | vsauce
    Big thanks to Martin Archer for help with this episode. And thanks to Guy Larsen for his shadow magic.
  • All (known) Bodies in our Solar System Larger than 200 Miles in Diameter (88 in all) - (pic)

    07/27/2014 11:23:33 AM PDT · by LibWhacker · 34 replies
  • Astronomy Picture of the Day -- Rho Ophiuchi Wide Field

    07/27/2014 6:48:52 AM PDT · by SunkenCiv · 4 replies
    NASA ^ | July 27, 2014 | (see photo credit)
    Explanation: The clouds surrounding the star system Rho Ophiuchi compose one of the closest star forming regions. Rho Ophiuchi itself is a binary star system visible in the light-colored region on the image right. The star system, located only 400 light years away, is distinguished by its colorful surroundings, which include a red emission nebula and numerous light and dark brown dust lanes. Near the upper right of the Rho Ophiuchi molecular cloud system is the yellow star Antares, while a distant but coincidently-superposed globular cluster of stars, M4, is visible between Antares and the red emission nebula. Near the...
  • Astronomy Picture of the Day -- NGC 253: Dusty Island Universe

    07/27/2014 6:47:45 AM PDT · by SunkenCiv · 3 replies
    NASA ^ | July 26, 2014 | (see photo credit)
    Explanation: Shiny NGC 253 is one of the brightest spiral galaxies visible, and also one of the dustiest. Some call it the Silver Dollar Galaxy for its appearance in small telescopes, or just the Sculptor Galaxy for its location within the boundaries of the southern constellation Sculptor. First swept up in 1783 by mathematician and astronomer Caroline Herschel, the dusty island universe lies a mere 10 million light-years away. About 70 thousand light-years across, NGC 253 is the largest member of the Sculptor Group of Galaxies, the nearest to our own Local Group of Galaxies. In addition to its spiral...
  • Astronomy Picture of the Day -- Cosmic Crab Nebula

    07/26/2014 8:29:05 AM PDT · by SunkenCiv · 7 replies
    NASA ^ | July 25, 2014 | (see photo credit)
    Explanation: The Crab Pulsar, a city-sized, magnetized neutron star spinning 30 times a second, lies at the center of this tantalizing wide-field image of the Crab Nebula. A spectacular picture of one of our Milky Way's supernova remnants, it combines optical survey data with X-ray data from the orbiting Chandra Observatory. The composite was created as part of a celebration of Chandra's 15 year long exploration of the high energy cosmos. Like a cosmic dynamo the pulsar powers the X-ray and optical emission from the nebula, accelerating charged particles to extreme energies to produce the jets and rings glowing in...
  • Having Fun with the Equation of Time

    07/25/2014 8:04:18 PM PDT · by BenLurkin · 9 replies
    universetoday.com ^ | July 25, 2014 | David Dickinson on
    That funky figure eight [on a globe] is what’s known as an analemma, and it traces out the course of the Sun in the sky through the year as measured from a daily point fixed in apparent solar time. ... Solar Noon occurs when the Sun stands at its highest elevation (also known as its altitude) above the local horizon when it transits the north-south meridian. The trouble is, the passage apparent solar time doesn’t exactly match what we call solar mean time, or the 24 hour rotation of the Earth. In fact, this discrepancy can add up to as...