Keyword: astronomy

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  • Astronomy Picture of the Day -- Moon, Venus and Planet Earth

    09/19/2013 3:59:51 AM PDT · by SunkenCiv · 3 replies
    NASA ^ | September 19, 2013 | (see photo credit)
    Explanation: In this engaging scene from planet Earth, the Moon shines through cloudy skies following sunset on the evening of September 8. Despite the fading light, the camera's long exposure still recorded a colorful, detailed view of a shoreline and western horizon looking toward the island San Gabriel from Colonia del Sacramento, Uruguay. Lights from Buenos Aires, Argentina are along the horizon on the left, across the broad Rio de la Plata estuary. The long exposure strongly overexposed the Moon and sky around it, though. So the photographer quickly snapped a shorter one to merge with the first image in...
  • Astronomy Picture of the Day -- M45: The Pleiades Star Cluster

    09/18/2013 7:05:11 PM PDT · by SunkenCiv · 9 replies
    NASA ^ | September 18, 2013 | (see photo credit)
    Explanation: Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as dusty as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen without binoculars from even the depths of a light-polluted city. With a long exposure from a dark location, though, the dust cloud surrounding the Pleiades star cluster becomes very evident. The above exposure took about 20 minutes and covers a sky area several times the size of the full moon. Also known as the Seven Sisters and M45, the...
  • Astronomy Picture of the Day -- Galaxy Cluster Abell 1689 Deflects Light

    09/17/2013 3:58:07 AM PDT · by SunkenCiv · 4 replies
    NASA ^ | September 17, 2013 | (see photo credit)
    Explanation: It is one of the most massive objects in the visible universe. In this view from the Hubble Space Telescope's Advanced Camera for Surveys, Abell 1689 is seen to warp space as predicted by Einstein's theory of gravity -- deflecting light from individual galaxies which lie behind the cluster to produce multiple, curved images. The power of this enormous gravitational lens depends on its mass, but the visible matter, in the form of the cluster's yellowish galaxies, only accounts for about one percent of the mass needed to make the observed bluish arcing images of background galaxies. In fact,...
  • Astronomy Picture of the Day -- Rotating Moon from LRO

    09/16/2013 6:05:02 PM PDT · by SunkenCiv · 12 replies
    NASA ^ | September 16, 2013 | (see photo credit)
    Explanation: No one, presently, sees the Moon rotate like this. That's because the Earth's moon is tidally locked to the Earth, showing us only one side. Given modern digital technology, however, combined with many detailed images returned by the Lunar Reconnaissance Orbiter (LRO), a high resolution virtual Moon rotation movie has now been composed. The above time-lapse video starts with the standard Earth view of the Moon. Quickly, though, Mare Orientale, a large crater with a dark center that is difficult to see from the Earth, rotates into view just below the equator. From an entire lunar month condensed into...
  • Astronomy Picture of the Day -- M2-9: Wings of a Butterfly Nebula

    09/14/2013 9:25:16 PM PDT · by SunkenCiv · 13 replies
    NASA ^ | September 15, 2013 | (see photo credit)
    Explanation: Are stars better appreciated for their art after they die? Actually, stars usually create their most artistic displays as they die. In the case of low-mass stars like our Sun and M2-9 pictured above, the stars transform themselves from normal stars to white dwarfs by casting off their outer gaseous envelopes. The expended gas frequently forms an impressive display called a planetary nebula that fades gradually over thousand of years. M2-9, a butterfly planetary nebula 2100 light-years away shown in representative colors, has wings that tell a strange but incomplete tale. In the center, two stars orbit inside a...
  • Astronomy Picture of the Day -- A Landing on Planet Earth

    09/14/2013 5:43:54 AM PDT · by SunkenCiv · 14 replies
    NASA ^ | September 14, 2013 | (see photo credit)
    Explanation: With parachute deployed and retro-rockets blazing, this spacecraft landed on planet Earth on September 11 (UT) in a remote area near the town of Zhezkazgan, Kazakhstan. Seen in silhouette against the rockets' glare, the spacecraft is a Soyuz TMA-08M. Its crew, Expedition 36 Commander Pavel Vinogradov and Flight Engineer Alexander Misurkin of the Russian Federal Space Agency (Roscosmos), and Flight Engineer Chris Cassidy of NASA were returning after five and half months aboard the International Space Station. The Soyuz retro-rockets fire very quickly and for an extremely short duration near touchdown. Capturing the moment, the well-timed photograph was taken...
  • Astronomy Picture of the Day -- Crescent Moon Meets Evening Star

    09/13/2013 5:39:53 PM PDT · by SunkenCiv · 10 replies
    NASA ^ | September 13, 2013 | (see photo credit)
    Explanation: On September 8, brilliant planet Venus appearing as the evening star stood near a slender, crescent Moon at sunset. The close celestial pairing or conjunction was a scene enjoyed by skygazers around the world. But from some locations in South America, the Moon actually passed in front of Venus in a lunar occultation. Captured near Las Cańas, Uruguay, this two frame mosaic telescopic view shows the Moon and Venus before and after the occultation. The silvery evening star appears at right just before it winked out behind the dark lunar limb, still in bright twilight skies. About an hour...
  • Astronomy Picture of the Day -- Stars and Dust Across Corona Australis

    09/12/2013 6:06:33 AM PDT · by SunkenCiv · 6 replies
    NASA ^ | September 12, 2013 | (see photo credit)
    Explanation: Cosmic dust clouds sprawl across a rich field of stars in this sweeping telescopic vista near the northern boundary of Corona Australis, the Southern Crown. Less than 500 light-years away the dust clouds effectively block light from more distant background stars in the Milky Way. The entire frame spans about 2 degrees or over 15 light-years at the clouds' estimated distance. Near center is a group of lovely reflection nebulae cataloged as NGC 6726, 6727, 6729, and IC 4812. A characteristic blue color is produced as light from hot stars is reflected by the cosmic dust. The dust also...
  • Astronomy Picture of the Day -- LADEE Launch Streak

    09/11/2013 3:49:01 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | September 11, 2013 | (see photo credit)
    Explanation: On September 6, a starry night and the Milky Way witnessed the launch of a Minotaur V rocket from NASA's Wallops Flight Facility on Wallops Island, Virginia. So did a large part of the eastern United States, as the spectacular night launch was easily visible even from light polluted urban areas. This 35 second exposure captures part of the rocket's initial launch streak and 2nd stage ignition flare along with a brilliant reflection of the fiery sky in calm waters. The stunning view faces south and west from a vantage point overlooking Sinepuxent Bay in Maryland about 20 miles...
  • Astronomy Picture of the Day -- Extrasolar Super-Earth Gliese 1214b Might Hold Water

    09/10/2013 3:49:55 AM PDT · by SunkenCiv · 12 replies
    NASA ^ | September 10, 2013 | (see photo credit)
    Explanation: Might this distant planet hold water? Actually, given how close Gliese 1214b is to its parent star, any water, if it exists, would surely be in the form of steam. In the above artist's illustration, the super-Earth Gliese 1214b is imagined passing in front of its parent star, creating a mini-eclipse that alerted humanity to its presence. Gliese 1214b, also designated GJ 1214b, has been designated a super-Earth because it is larger than the Earth but smaller a planet like Neptune. The entire Gliese 1214 planetary system is of the closest known systems to our Sun, located only 42...
  • Astronomy Picture of the Day -- Nearby Cepheid Variable RS Pup

    09/09/2013 7:42:32 PM PDT · by SunkenCiv · 3 replies
    NASA ^ | September 09, 2013 | (see photo credit)
    Explanation: It is one of the most important stars in the sky. This is partly because, by coincidence, it is surrounded by a dazzling reflection nebula. Pulsating RS Puppis, the brightest star in the image center, is some ten times more massive than our Sun and on average 15,000 times more luminous. In fact, RS Pup is a Cepheid type variable star, a class of stars whose brightness is used to estimate distances to nearby galaxies as one of the first steps in establishing the cosmic distance scale. As RS Pup pulsates over a period of about 40 days, its...
  • Trayvon Martin Might Have a WHAT Named in His Honor?

    09/09/2013 3:39:56 PM PDT · by 2ndDivisionVet · 45 replies
    EURWEB ^ | September 9, 2013
    *A trustee for the Lowell Observatory in Flagstaff, Arizona wants to honor the memory of Trayvon Martin by naming an asteroid after him. William Lowell Putnam III told the Arizona Daily Sun he wants to place Martin’s name on one of the hundreds of asteroids discovered by the Lowell observatory in 2000. This is what the proposed citation for 2000 TM61 reads: “Named in memory of Trayvon Martin (1995-2012), a student at Dr. Michael M. Krop High School in Miami, Florida. Unarmed, he was fatally shot in Sanford, Florida, during an altercation with the neighborhood watch coordinator.” Putman had pushed...
  • Astronomy Picture of the Day -- Roll Cloud Over Wisconsin

    09/08/2013 11:59:58 AM PDT · by SunkenCiv · 20 replies
    NASA ^ | September 08, 2013 | (see photo credit)
    Explanation: What kind of cloud is this? A type of arcus cloud called a roll cloud. These rare long clouds may form near advancing cold fronts. In particular, a downdraft from an advancing storm front can cause moist warm air to rise, cool below its dew point, and so form a cloud. When this happens uniformly along an extended front, a roll cloud may form. Roll clouds may actually have air circulating along the long horizontal axis of the cloud. A roll cloud is not thought to be able to morph into a tornado. Unlike a similar shelf cloud, a...
  • Astronomy Picture of the Day -- Night in the Andes Ice Forest

    09/08/2013 11:58:50 AM PDT · by SunkenCiv · 12 replies
    NASA ^ | September 07, 2013 | (see photo credit)
    Explanation: This forest of snow and ice penitentes reflects moonlight shining across the Chajnantor plateau. The region lies in the Chilean Andes at an altitude of 5,000 meters, not far from one of planet Earth's major astronomical observatories, the Atacama Large Millimeter/submillimeter Array. Up to several meters high, the flattened, sharp-edged shapes, and orientation of the penitentes tend to minimize their shadows at local noon. In the dry, cold, thin atmosphere, sublimation driven by sunlight is important for their formation. A direct transition from a solid to a gaseous state, sublimation shapes other solar system terrains too, like icy surfaces...
  • Astronomy Picture of the Day -- The Quiet Sagittarius A*

    09/08/2013 11:57:55 AM PDT · by SunkenCiv · 5 replies
    NASA ^ | September 06, 2013 | (see photo credit)
    Explanation: Hot gas is hard to swallow. At least that seems to be true for the supermassive black hole at the center of our Milky Way Galaxy. Known as source Sagittarius A*, the Milky Way's black hole is centered in this infrared (red and yellow hues) and X-ray (blue) composite. Based on data from an extensive campaign of observations by the orbiting Chandra X-ray telescope, the diffuse emission surrounding the black hole is seen in the close-up inset, the inset field spanning about 1/2 light-year across the galactic center some 26,000 light-years away. Astronomers have found that the X-ray emission...
  • Moon probe has small glitch after launch, NASA says

    09/07/2013 11:29:29 AM PDT · by BenLurkin · 14 replies
    NBC ^ | 1 hour ago | Miriam Kramer, Space.com
    Although the launch was nearly flawless, LADEE ran into some trouble right after its separation from the Minotaur V. The probe's onboard computer shut down LADEE's reaction wheels, which are used to stabilize the attitude of the probe in space, after noticing that they were drawing too much current. Engineers will work to develop a repair plan over the next few days. But there's not a great deal of time pressure at the moment, Worden said. LADEE will take nearly a month to get to the moon on its long and looping route. "The nice thing about this is that...
  • Astronomy Picture of the Day -- M1: The Incredible Expanding Crab

    09/05/2013 7:37:34 PM PDT · by SunkenCiv · 7 replies
    NASA ^ | September 05, 2013 | (see photo credit)
    Explanation: The Crab Nebula is cataloged as M1, the first on Charles Messier's famous list of things which are not comets. In fact, the Crab is now known to be a supernova remnant, an expanding cloud of debris from the explosion of a massive star. The violent birth of the Crab was witnessed by astronomers in the year 1054. Roughly 10 light-years across today, the nebula is still expanding at a rate of over 1,000 kilometers per second. Want to watch the Crab Nebula expand? Check out this video (vimeo) animation comparing an image of M1 taken in 1999 at...
  • Astronomy Picture of the Day -- IRAS 20324: Evaporating Protostar

    09/04/2013 4:04:22 PM PDT · by SunkenCiv · 12 replies
    NASA ^ | September 04, 2013 | (see photo credit)
    Explanation: Will this caterpillar-shaped interstellar cloud one day evolve into a butterfly-shaped nebula? No one is sure. What is sure is that IRAS 20324+4057, on the inside, is contracting to form a new star. On the outside, however, energetic winds are blowing and energetic light is eroding away much of the gas and dust that might have been used to form the star. Therefore, no one is sure what mass the resulting star will have, and, therefore, no one knows the fate of this star. Were the winds and light to whittle the protostar down near the mass of the...
  • Astronomy Picture of the Day -- North America and the Pelican

    09/03/2013 4:28:42 PM PDT · by SunkenCiv · 7 replies
    NASA ^ | September 03, 2013 | (see photo credit)
    Explanation: Here lie familiar shapes in unfamiliar locations. On the left is an emission nebula cataloged as NGC 7000, famous partly because it resembles our fair planet's continent of North America. The emission region to the right of the North America Nebula is IC 5070, also known for its suggestive outlines as the Pelican Nebula. Separated by a dark cloud of obscuring dust, the two bright nebulae are about 1,500 light-years away. At that distance, the 4 degree wide field of view spans 100 light-years. This spectacular cosmic portrait combines narrow band images to highlight bright ionization fronts with fine...
  • Astronomy Picture of the Day -- Milky Way Over Spain's Bardenas Reales

    09/02/2013 12:33:43 PM PDT · by SunkenCiv · 15 replies
    NASA ^ | September 02, 2013 | (see photo credit)
    Explanation: What's that below the Milky Way? First, across the top of the above image, lies the faint band that is our planet's sideways view of the central disk of our home Milky Way Galaxy. The Milky Way band can be seen most clear nights from just about anywhere on Earth with a dark sky. What lies beneath is, by comparison, is a much less common sight. It is the striking peak of Castildetierra, a rock formation located in Bardenas Reales, a natural badlands in northeast Spain. Standing 50 meters tall, the rock spire includes clay and sandstone left over...
  • Astronomy Picture of the Day -- Fire on Earth [from year 2000]

    08/31/2013 9:14:15 PM PDT · by SunkenCiv · 10 replies
    NASA ^ | September 01, 2013 | (see photo credit)
    Explanation: Sometimes, regions of planet Earth light up with fire. Since fire is the rapid acquisition of oxygen, and since oxygen is a key indicator of life, fire on any planet would be an indicator of life on that planet. Most of the Earth's land has been scorched by fire at some time in the past. Although causing many a tragedy, for many places on Earth fire is considered part of a natural ecosystem cycle. Large forest fires on Earth are usually caused by lightning and can be visible from orbit. Above, in the year 2000, stunned elk avoid a...
  • Astronomy Picture of the Day -- NGC 5195: The Dot Under the Question Mark

    08/31/2013 6:19:59 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | August 31, 2013 | (see photo credit)
    Explanation: Dwarf galaxy NGC 5195 is best known as the smaller companion of spiral M51, the Whirlpool galaxy. Seen together they seem to trace the curve and dot of a cosmic question mark, recorded in Lord Rosse's 19th century drawings as one of the original spiral nebulae. Dwarfed by enormous M51 (aka NGC 5194), NGC 5195 spans about 20,000 light-years. A close encounter with M51 has likely triggered star formation and enhanced that galaxy's prominent spiral arms. Processed from image data available in the Hubble Legacy Archive, this majestic close-up of NGC 5195 makes it clear that the dwarf galaxy...
  • Astronomy Picture of the Day -- A Sagittarius Triplet

    08/30/2013 7:49:25 PM PDT · by SunkenCiv · 2 replies
    NASA ^ | August 30, 2013 | (see photo credit)
    Explanation: These three bright nebulae are often featured in telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. In fact, 18th century cosmic tourist Charles Messier cataloged two of them; M8, the large nebula left of center, and colorful M20 on the right. The third, NGC 6559, is above M8, separated from the larger nebula by a dark dust lane. All three are stellar nurseries about five thousand light-years or so distant. The expansive M8, over a hundred light-years across, is also known as the Lagoon Nebula. M20's popular moniker is the Trifid. Glowing...
  • Astronomy Picture of the Day -- Strawberry Sun

    08/29/2013 3:58:38 AM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 29, 2013 | (see photo credit)
    Explanation: This striking, otherworldy scene really is a view from planet Earth. The ochre sky and strawberry red sun were photographed on August 22nd near the small village of Strawberry, California, USA. Found along Highway 108, that location is about 30 miles north of the origin of California's large Rim Fire, still threatening areas in and around Yosemite National Park. The extensive smoke plumes from the wildfire are easily visible from space. But seen from within the plumes, the fine smoke particles suspended in the atmosphere dim the Sun, scattering blue light and strongly coloring the sky.
  • Astronomy Picture of the Day -- A Retreating Thunderstorm at Sunset

    08/28/2013 3:43:38 AM PDT · by SunkenCiv · 9 replies
    NASA ^ | August 28, 2013 | (see photo credit)
    Explanation: What type of cloud is that? This retreating cumulonimbus cloud, more commonly called a thundercloud, is somewhat unusual as it contains the unusual bumpiness of a mammatus cloud on the near end, while simultaneously producing falling rain on the far end. Taken in mid-June in southern Alberta, Canada, the cloud is moving to the east, into the distance, as the sun sets in the west, behind the camera. In the above image, graphic sunset colors cross the sky to give the already photogenic cloud striking orange and pink hues. A darkening blue sky covers the background. Further in the...
  • Astronomy Picture of the Day -- A Flight through the Hubble Ultra Deep Field

    08/27/2013 3:54:48 AM PDT · by SunkenCiv · 6 replies
    NASA ^ | August 27, 2013 | (see photo credit)
    Explanation: What would it look like to fly through the distant universe? To find out, a team of astronomers estimated the relative distances to over 5,000 galaxies in one of the most distant fields of galaxies ever imaged: the Hubble Ultra Deep Field (HUDF). Because it takes light a long time to cross the universe, most galaxies visible in the above video are seen when the universe was only a fraction of its current age, were still forming, and have unusual shapes when compared to modern galaxies. No mature looking spiral galaxies such as our Milky Way or the Andromeda...
  • Astronomy Picture of the Day -- Bright Planetary Nebula NGC 7027 from Hubble

    08/26/2013 3:59:07 AM PDT · by SunkenCiv · 8 replies
    NASA ^ | August 26, 2013 | (see photo credit)
    Explanation: It is one of the brightest planetary nebulae on the sky -- what should it be named? First discovered in 1878, nebula NGC 7027 can be seen toward the constellation of the Swan (Cygnus) with a standard backyard telescope. Partly because it appears there as only an indistinct spot, it is rarely referred to with a moniker. When imaged with the Earth-orbiting Hubble Space Telescope, however, great details are revealed. Studying Hubble images of NGC 7027 have led to the understanding that it is a planetary nebula that began expanding about 600 years ago, and that the cloud of...
  • Astronomy Picture of the Day -- The Colliding Spiral Galaxies of Arp 271

    08/25/2013 6:08:42 AM PDT · by SunkenCiv · 12 replies
    NASA ^ | August 25, 2013 | (see photo credit)
    Explanation: What will become of these galaxies? Spiral galaxies NGC 5426 and NGC 5427 are passing dangerously close to each other, but each is likely to survive this collision. Typically when galaxies collide, a large galaxy eats a much smaller galaxy. In this case, however, the two galaxies are quite similar, each being a sprawling spiral with expansive arms and a compact core. As the galaxies advance over the next tens of millions of years, their component stars are unlikely to collide, although new stars will form in the bunching of gas caused by gravitational tides. Close inspection of the...
  • Astronomy Picture of the Day -- Earth Waves at Saturn

    08/24/2013 4:09:06 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 24, 2013 | (see photo credit)
    Explanation: This friendly photo collage is constructed from more than 1,400 images shared by denizens of planet Earth as part of the Cassini Mission's July 19th Wave at Saturn event. The base picture of Earth corresponds to the view from the Saturn-orbiting Cassini spacecraft on that date as its own cameras recorded images including planet Earth as a pale blue dot in the background. Of course, Saturn was 9.65 Astronomical Units away at the time, so it took light from all the waving Earth dwellers just over 80 minutes to travel there. Want to smile? Download and zoom in to...
  • Astronomy Picture of the Day -- A Spectrum of Nova Delphini

    08/24/2013 4:09:03 PM PDT · by SunkenCiv · 2 replies
    NASA ^ | August 23, 2013 | (see photo credit)
    Explanation: When a new star appeared in the constellation Delphinus late last week, astronomers found its spectrum hinted at the apparition's true nature. Now known as Nova Delphini 2013, its visible light spectrum near maximum brightness is centered in this image of the nearby star field captured with prism and telescope on the night of August 16/17 at the Sternwarte Bülach, Switzerland. Strong absorption lines due to hydrogen atoms are seen as the darkest bands in the nova's spectrum, but the strong absorption lines are bordered along their redward edge by bright bands of emission. That pattern is the spectral...
  • Astronomy Picture of the Day -- IC 5067 in the Pelican Nebula

    08/22/2013 7:49:40 PM PDT · by SunkenCiv · 12 replies
    NASA ^ | August 22, 2013 | (see photo credit)
    Explanation: The prominent ridge of emission featured in this dramatic skyscape is cataloged as IC 5067. Part of a larger emission nebula with a distinctive shape, popularly called The Pelican Nebula, the ridge spans about 10 light-years following the curve of the cosmic pelican's head and neck. This false color view also translates the pervasive glow of narrow emission lines from atoms in the nebula to a color palette made popular in Hubble Space Telescope images of star forming regions. Fantastic, dark shapes inhabiting the 1/2 degree wide field are clouds of cool gas and dust sculpted by the winds...
  • Astronomy Picture of the Day -- Perseid Meteors Over China

    08/20/2013 9:20:57 PM PDT · by SunkenCiv · 4 replies
    NASA ^ | August 21, 2013 | (see photo credit)
    Explanation: Comet dust rained down on planet Earth earlier this month, streaking through dark skies in the annual Perseid meteor shower. While enjoying the anticipated space weather above Zhangbei Prairie, Hebei Province, China, astronomer Xiang Zhan recorded a series of 10 second long exposures spanning four hours on the night of August 12/13 using a wide angle lens. Combining frames which captured 68 meteor flashes, he produced the above composite view of the Perseids of summer. Although the sand-sized comet particles are traveling parallel to each other, the resulting shower meteors clearly seem to radiate from a single point on...
  • Astronomy Picture of the Day -- Venus and the Triply Ultraviolet Sun

    08/20/2013 9:20:54 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 20, 2013 | (see photo credit)
    Explanation: An unusual type of solar eclipse occurred last year. Usually it is the Earth's Moon that eclipses the Sun. Last June, most unusually, the planet Venus took a turn. Like a solar eclipse by the Moon, the phase of Venus became a continually thinner crescent as Venus became increasingly better aligned with the Sun. Eventually the alignment became perfect and the phase of Venus dropped to zero. The dark spot of Venus crossed our parent star. The situation could technically be labeled a Venusian annular eclipse with an extraordinarily large ring of fire. Pictured above during the occultation, the...
  • Astronomy Picture of the Day -- Noctilucent Clouds and Aurora Over Scotland

    08/19/2013 2:58:23 PM PDT · by SunkenCiv · 3 replies
    NASA ^ | August 19, 2013 | (see photo credit)
    Explanation: Why would the sky still glow after sunset? Besides stars and the band of our Milky Way galaxy, the sky might glow because it contains either noctilucent clouds or aurora. Rare individually, both are visible in the above time lapse movie taken over Caithness, Scotland, UK taken during a single night earlier this month. First noted in 1885, many noctilucent clouds are known to correlate with atmospheric meteor trails, although details and the origins of others remain a topic of research. These meandering bright filaments of sunlight-reflecting ice crystals are the highest clouds in the Earth's atmosphere. The above...
  • Astronomy Picture of the Day -- Skylab Over Earth

    08/18/2013 5:52:51 AM PDT · by SunkenCiv · 33 replies
    NASA ^ | August 18, 2013 | (see photo credit)
    Explanation: Skylab was an orbiting laboratory launched by a Saturn V rocket in May 1973. Skylab, pictured above, was visited three times by NASA astronauts who sometimes stayed as long as two and a half months. Many scientific tests were performed on Skylab, including astronomical observations in ultraviolet and X-ray light. Some of these observations yielded valuable information about Comet Kohoutek, our Sun and about the mysterious X-ray background -- radiation that comes from all over the sky. Skylab fell back to earth on 1979 July 11.
  • World's oldest temple built to worship the dog star

    08/17/2013 4:28:29 AM PDT · by SunkenCiv · 44 replies
    New Scientist ^ | Friday, August 16, 2013 | Anil Ananthaswamy
    Magli simulated what the sky would have looked like from Turkey when Göbekli Tepe was built. Over millennia, the positions of the stars change due to Earth wobbling as it spins on its axis. Stars that are near the horizon will rise and set at different points, and they can even disappear completely, only to reappear thousands of years later. Today, Sirius can be seen almost worldwide as the brightest star in the sky -- excluding the sun -- and the fourth brightest night-sky object after the moon, Venus and Jupiter. Sirius is so noticeable that its rising and setting...
  • Astronomy Picture of the Day -- M8: The Lagoon Nebula

    08/17/2013 3:54:57 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | August 17, 2013 | (see photo credit)
    Explanation: This beautiful cosmic cloud is a popular stop on telescopic tours of the constellation Sagittarius. Eighteenth century cosmic tourist Charles Messier cataloged the bright nebula as M8. Modern day astronomers recognize the Lagoon Nebula as an active stellar nursery about 5,000 light-years distant, in the direction of the center of our Milky Way Galaxy. Hot stars in the embedded open star cluster NGC 6530 power the nebular glow. Remarkable features can be traced through this sharp picture, showing off the Lagoon's filaments of glowing gas and dark dust clouds. Twisting near the center of the Lagoon, the small, bright...
  • Astronomy Picture of the Day -- Nova Delphini 2013

    08/16/2013 4:07:59 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | August 16, 2013 | (see photo credit)
    Explanation: Using a small telescope to scan the skies on August 14, Japanese amateur astronomer Koichi Itagaki discovered a "new" star within the boundaries of the constellation Delphinus. Indicated in this skyview captured on August 15 from Stagecoach, Colorado, it is now appropriately designated Nova Delphini 2013. Sagitta, the Arrow, points the way to the newcomer's location high in the evening sky, not far from bright star Altair and the asterism known to northern hemisphere skygazers as the Summer Triangle. The nova is reported to be easy to spot with binoculars, near the limit of naked-eye visibility under dark skies....
  • Astronomy Picture of the Day -- The Magellanic Stream

    08/16/2013 4:07:16 AM PDT · by SunkenCiv · 14 replies
    NASA ^ | August 15, 2013 | (see photo credit)
    Explanation: In an astronomical version of the search for the source of the Nile, astronomers now have strong evidence for the origin of the Magellanic Stream. This composite image shows the long ribbon of gas, discovered at radio wavelengths in the 1970s, in pinkish hues against an optical all-sky view across the plane of our Milky Way galaxy. Both Large and Small Magellanic Clouds, dwarf satellite galaxies of the the Milky Way, are seen near the head of the stream at the right. Data from Hubble's Cosmic Origins Spectrograph were used to explore abundances of elements along sightlines to quasars...
  • Astronomy Picture of the Day -- Moonset from Taiwan

    08/14/2013 3:12:26 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | August 14, 2013 | (see photo credit)
    Explanation: It took three worlds to create this simple image. The first world was the Earth, which was quite prominent. The dividing line running horizontally below the middle separates sea from sky. On this part of the Earth, it was almost nighttime. The second world was the Moon, which was almost invisible. The Moon had its unilluminated half masked by the red sunset glow of Earth's sky. A thin sliver of the new Moon was visible, a crescent that traces the bright curving line. The third world was the Sun, which does not appear directly. All of the light recorded...
  • Astronomy Picture of the Day -- Perseid Meteors Over Ontario

    08/13/2013 3:32:37 AM PDT · by SunkenCiv · 7 replies
    NASA ^ | August 13, 2013 | (see photo credit)
    Explanation: Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Perseus. That is why the meteor shower that peaked over the past few days is known as the Perseids -- the meteors all appear to come from a radiant toward Perseus. Three dimensionally, however, sand-sized debris expelled from Comet Swift-Tuttle follows a well-defined orbit about our Sun, and the part of the orbit that approaches Earth is superposed in front of the Perseus. Therefore, when Earth crosses this orbit, the radiant point of falling debris appears in...
  • Astronomy Picture of the Day -- Orbits of Potentially Hazardous Asteroids

    08/12/2013 3:44:40 AM PDT · by SunkenCiv · 15 replies
    NASA ^ | August 12, 2013 | (see photo credit)
    Explanation: Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth. Pictured above are the orbits of the over 1,000 known Potentially Hazardous Asteroids (PHAs). These documented tumbling boulders of rock and ice are over 140 meters across and will pass within 7.5 million kilometers of Earth -- about 20 times the distance to the Moon....
  • Astronomy Picture of the Day -- M74: The Perfect Spiral

    08/12/2013 3:44:34 AM PDT · by SunkenCiv · 7 replies
    NASA ^ | August 11, 2013 | (see photo credit)
    Explanation: If not perfect, then this spiral galaxy is at least one of the most photogenic. An island universe of about 100 billion stars, 32 million light-years away toward the constellation Pisces, M74 presents a gorgeous face-on view. Classified as an Sc galaxy, the grand design of M74's graceful spiral arms are traced by bright blue star clusters and dark cosmic dust lanes. Constructed from image data recorded in 2003 and 2005, this sharp composite is from the Hubble Space Telescope's Advanced Camera for Surveys. Spanning about 30,000 light-years across the face of M74, it includes exposures recording emission from...
  • Astronomy Picture of the Day -- Perseids over Meteora

    08/10/2013 2:36:00 PM PDT · by SunkenCiv · 10 replies
    NASA ^ | August 10, 2013 | (see photo credit)
    Explanation: The two bright meteors flashing through this night skyscape from August 7 are part of the ongoing Perseid meteor shower. In the direction indicated by both colorful streaks, the shower's radiant in the eponymous constellation Perseus is at the upper right. North star Polaris, near the center of all the short, arcing star trails is at the upper left. But also named for its pose against the sky, the monastery built on the daunting sandstone cliffs in the foreground is part of Meteora. A World Heritage site, Meteora is a historic complex of lofty monasteries located near Kalabaka in...
  • Astronomy Picture of the Day -- Perseid over Albrechtsberg Castle

    08/10/2013 2:35:55 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 09, 2013 | (see photo credit)
    Explanation: Medieval Albrechtsberg castle is nestled in trees near the northern bank of the river Pielach and the town of Melk, Austria. In clearing night skies on August 12, 2012 it stood under constellations of the northern summer, including Aquarius, Aquila, and faint, compact Delphinus (above and right of center) in this west-looking skyview. The scene also captures a bright meteor above the castle walls. Part of the annual perseid meteor shower, its trail points back toward the heroic constellation Perseus high above the horizon in the early morning hours. Entering the atmosphere at about 60 kilometers per second, perseid...
  • Astronomy Picture of the Day -- NGC 3370: A Sharper View

    08/07/2013 9:37:45 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 08, 2013 | (see photo credit)
    Explanation: Similar in size and grand design to our own Milky Way, spiral galaxy NGC 3370 lies about 100 million light-years away toward the constellation Leo. Recorded here in exquisite detail by the Hubble Space Telescope's Advanced Camera for Surveys, the big, beautiful face-on spiral does steal the show, but the sharp image also reveals an impressive array of background galaxies in the field, strewn across the more distant Universe. Looking within NGC 3370, the image data has proved sharp enough to study individual pulsating stars known as Cepheids that can be used to accurately determine this galaxy's distance. NGC...
  • Astronomy Picture of the Day -- Meteors and Aurorae over Iceland

    08/07/2013 9:35:43 PM PDT · by SunkenCiv · 7 replies
    NASA ^ | August 07, 2013 | (see photo credit)
    Explanation: What's going on behind that mountain? Quite a bit. First of all, the mountain itself, named Kirkjufell, is quite old and located in western Iceland near the town of Grundarfj%C3%B6r%C3%B0ur. In front of the steeply-sloped structure lies a fjord that had just begun to freeze when the above image was taken -- in mid-December of 2012. Although quite faint to the unaided eye, the beautiful colors of background aurorae became quite apparent on the 25-second exposure. What makes Geminids meteor shower -- meteors that might not have been evident were the aurora much brighter. Far in the distance, on...
  • Astronomy Picture of the Day -- In the Vicinity of the Cone Nebula

    08/06/2013 6:48:08 PM PDT · by SunkenCiv · 20 replies
    NASA ^ | August 06, 2013 | (see photo credit)
    Explanation: Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars. The brightest star on the right of the above picture is S Mon, while the region just below it has been nicknamed the Fox Fur Nebula for its color and structure. The blue glow directly surrounding S Mon results from reflection, where neighboring dust reflects light from the bright star. The red glow that encompasses the whole region results not only...
  • The Age of the Universe

    08/05/2013 6:15:40 PM PDT · by wmfights · 158 replies
    GeraldSchroeder.com ^ | Gerald Schroeder
    We look back in time, and say the universe is 15 billion years old. But as every scientist knows, when we say the universe is 15 billion years old, there's another half of the sentence that we rarely bother to say. The other half of the sentence is: The universe is 15 billion years old as seen from the time-space coordinates of the earth. The key is that the Torah looks forward in time, from very different time-space coordinates, when the universe was small. Since then, the universe has expanded out. Space stretches, and that stretching of space totally changes...
  • Astronomy Picture of the Day -- Leaving Earth

    08/05/2013 3:59:08 AM PDT · by SunkenCiv · 20 replies
    NASA ^ | August 05, 2013 | (see photo credit)
    Explanation: What it would look like to leave planet Earth? Such an event was recorded visually in great detail by the MESSENGER spacecraft as it swung back past the Earth, eight years ago, on its way in toward the planet Mercury. Earth can be seen rotating in this time-lapse video, as it recedes into the distance. The sunlit half of Earth is so bright that background stars are not visible. The robotic MESSENGER spacecraft is now in orbit around Mercury and has recently concluded the first complete map of the surface. On occasion, MESSENGER has continued to peer back at...