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Εργαλεία Θεμάτων | Τρόποι εμφάνισης |
#676
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Irregular Galaxy NGC 55 Credit & Copyright: Robert Gendler Explanation: Irregular galaxy NGC 55 is thought to be similar to the Large Magellanic Cloud (LMC). But while the LMC is about 180,000 light-years away and is a well known satellite of our own Milky Way Galaxy, NGC 55 is more like 6 million light-years distant and is a member of the Sculptor Galaxy Group. Classified as an irregular galaxy, in deep exposures the LMC itself resembles a barred disk galaxy. However, spanning about 50,000 light-years, NGC 55 is seen nearly edge-on, presenting a flattened, narrow profile in contrast with our face-on view of the LMC. Just as large star forming regions create emission nebulae in the LMC, NGC 55 is also seen to be producing new stars. This gorgeous galaxy portrait highlights a bright core, telltale pinkish emission regions, and young blue star clusters in NGC 55. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα Τελευταία επεξεργασία από το χρήστη Xenios : 10-10-08 στις 08:47 |
#677
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Bright Bolide Credit & Copyright: Howard Edin (Oklahoma City Astronomy Club) Explanation: On September 30, a spectacular bolide or fireball meteor surprised a group of amateur astronomers enjoying dark night skies over the Oklahoma panhandle's Black Mesa State Park in the Midwestern US. Flashing past familiar constellations Taurus (top) and Orion, the extremely bright meteor was captured by a hillside camera overlooking the 2008 Okie-Tex Star Party. Astronomy enthusiast Howard Edin reports that he was looking in the opposite direction at the time, but saw the whole observing field light up and at first thought someone had turned on their car headlights. So far the sighting of a such a bright bolide meteor, produced as a space rock is vaporized hurtling through Earth's atmosphere, really is a matter of luck. But that could change. Earlier this week the discovery and follow-up tracking of tiny asteroid 2008 TC3 allowed astronomers to predict the time and location of its impact with the atmosphere. While no ground-based sightings of the fireball seem to have been reported, this first ever impact prediction was confirmed by at least some detections of an air burst and bright flash on October 7th over northern Sudan. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
#678
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Spiral Galaxy NGC 3370 from Hubble Credit: NASA, ESA, Hubble Heritage (STScI/AURA); Acknowledgement: A. Reiss et al. (JHU) Explanation: Is this what our own Milky Way Galaxy looks like from far away? Similar in size and grand design to our home Galaxy (although without the central bar), spiral galaxy NGC 3370 lies about 100 million light-years away toward the constellation of the Lion (Leo). Recorded above in exquisite detail by the Hubble Space Telescope's Advanced Camera for Surveys, the big, beautiful face-on spiral is not only photogenic, but has proven sharp enough to study individual stars known as Cepheids. These pulsating stars have been used to accurately determine NGC 3370's distance. NGC 3370 was chosen for this study because in 1994 the spiral galaxy was also home to a well studied stellar explosion -- a Type Ia supernova. Combining the known distance to this standard candle supernova, based on the Cepheid measurements, with observations of supernovas at even greater distances, has helped to reveal the size and expansion rate of the entire Universe itself. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
#679
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Cassini Passes Through Ice Plumes of Enceladus Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA Explanation: What telling impurities taint the ice plumes of Enceladus? To help answer this question, the robotic Cassini spacecraft dove last week to within 30 kilometers of Saturn's ice-plume emitting moon. At this closest-ever approach, Cassini attempted to sniff and obtain chemical data on particles ejected from Enceladus' regular surface, while at other times Cassini flew right through -- and sampled -- ice geysers directly. Searches in the data for impurity clues in the water-ice dominated plumes and surface ejecta are progressing. Although the main purpose of this flyby was particle analysis, several interesting images are emerging. Visible in the above image, for example, is an unusual gray sheen running vertically up the image center that might be water vapor escaping from surface canyons. Other notable features visible above include vast plains of craterless icy grooves, the day-night terminator across the image left, and an area near the top comparatively rich in craters. Cassini is scheduled to buzz by Enceladus in an imaging run near the end of this month. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
#680
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An Enceladus Tiger Stripe from Cassini Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA Explanation: What creates the unusual tiger stripes on Saturn's moon Enceladus? No one is sure. To help find out, scientists programmed the robotic Cassini spacecraft to dive right past the plume-spewing moon last week. Previously, the tiger stripe regions were found to be expelling plumes of water-ice, fueling speculation that liquid seas might occur beneath Enceladus' frozen exterior. Such seas are so interesting because they are candidates to contain extraterrestrial life. Important processes in tiger stripe formation may include heating from below and moonquakes. Visible above is terrain on Enceladus so young that only a few craters are visible. This newly released raw image shows at least one type of false artifact, however, as seeming chains of craters are not so evident in other concurrently released images of the same region. The large tiger stripe across the image middle is impressive not only for its length and breadth, but because a large internal shadow makes it also appear quite deep. Cassini will next fly by Enceladus on October 31. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
#681
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(κάνετε κλικ στην εικόνα, για μεγαλύτερη φωτογραφία) Camera Orion Credit & Copyright: John Gauvreau Explanation: Orion, the Hunter, is one of the most easily recognizable constellations in planet Earth's night sky. But Orion's stars and nebulas don't look quite as colorful to the eye as they do in this lovely camera image, taken early last month at the Black Forest Star Party from Cherry Springs State Park in Pennsylvania, USA. In this single exposure, cool red giant Betelgeuse takes on a yellowish tint as the brightest star at the far left. Otherwise Orion's hot blue stars are numerous, with supergiant Rigel balancing Betelgeuse at the upper right, Bellatrix at the upper left, and Saiph at the lower right. Lined up in Orion's belt (bottom to top) are Alnitak, Alnilam, and Mintaka all about 1,500 light-years away, born of the constellation's well studied interstellar clouds. And if the middle "star" of Orion's sword looks reddish and fuzzy to you, it should. It's the stellar nursery known as the Great Nebula of Orion. Πηγή
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VmF Skisters of Mercy © An eye for an eye, will make us all blind... Mahatma Ghandi |
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48 Years of Space Flight Credit & Copyright: Ralf Vandebergh Explanation: This year, NASA celebrated its 50th anniversary. Inspired to make his own contribution, astronomer Ralf Vandebergh set out to record images of some historic spacecraft in Earth orbit -- captured with his own modest equipment and a hand-guided, 10-inch, Newtonian reflecting telescope. One result is this intriguing composite effectively spanning 48 years of space flight! From a 1960 launch, on the left is the TIROS 2 satellite, one of the first successful weather satellites. While this TIROS (Television InfraRed Observation System) satellite stopped functioning in 1961, Vandeberg notes that if we could visit it now, we would still find video cameras and magnetic tape recorders. On the right, of course, is the ISS (International Space Station) including its recent addition, the Progress M-65 cargo vehicle, launched to the ISS just last month. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση An Extraordinary Voyage Credit: Jesse Carpenter, Bill Moede, Peter Jenniskens (NASA Ames Research Center) Explanation: Nineteenth century science fiction author Jules Verne wrote visionary works about Extraordinary Voyages including tales of space flight and the story of a journey From the Earth to the Moon. Fittingly, the European Space Agency's newly developed Automated Transfer Vehicle (ATV), a robotic spacecraft intended to deliver cargo to the International Space Station (ISS) was named in his honor and successfully docked with the ISS earlier this year. When the Jules Verne ATV was undocked and deorbited last month, its safely controlled reentry over the Pacific Ocean was followed by astronomers in order to make detailed comparisons of the actual event with computer models of spacecraft reentry and breakup in the atmosphere. This dramatic image of the fragmenting, 13-ton spacecraft is a high definition video frame recorded from NASA's DC-8 Airborne Laboratory. The observations were part of the joint ESA/NASA Jules Verne Multi-Instrument Aircraft Campaign. Πηγή Σχόλιο : Wow!!
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Sharpless 171 Credit & Copyright: Antonio Fernandez Explanation: Cosmic pillars of cold molecular gas and clouds of dark dust lie within Sharpless 171, a star-forming region some 3,000 light-years away in the royal constellation Cepheus. This tantalizing false-color skyscape spans about 20 light-years across the nebula's bright central region. It also highlights the pervasive glow of emission from atomic gas using narrowband filters and a color palette made popular in Hubble Space Telescope images. Powering the nebular glow are the young, hot stars of a newly formed cluster, Berkeley 59. Of course, this star-forming region is entry number 171 in the famous 1959 catalog of emission nebulae compiled by astronomer Stewart Sharpless. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση In the Center of the Lagoon Nebula Credit: A. Caulet (ST-ECF, ESA), NASA Explanation: The center of the Lagoon Nebula is a whirlwind of spectacular star formation. Visible on the upper left, 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, Hershel 36, lights the area. Vast 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, was taken in 1995 by the orbiting Hubble Space Telescope. The Lagoon Nebula, also known as M8, lies about 5000 light years distant toward the constellation of Sagittarius. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Moons, Rings, and Unexpected Colors on Saturn Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA Explanation: Why would Saturn show such strange colors? The robotic Cassini spacecraft currently orbiting Saturn has beamed back images showing that the northern hemisphere our Solar System's most spectacularly ringed planet has changed noticeably since Cassini arrived in 2004, now sporting unusual and unexpected colors. No one is sure why. Although the cause for many of Saturn's colors is unknown, the recent change in colors is thought to be related to the changing seasons. Pictured above, the unusual colors are visible just north of the dark ring shadows. The razor-thin plane of ring particles is visible nearly edge-on across the bottom of the image. The cloudy moon Titan looms large just above the rings, while close observation will reveal three other moons. Cassini arrived at Saturn in 2004, sending back data and images that have not only led to a deeper understanding of the Jovian world's atmosphere, moons, and rings, but also raised new mysteries. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση A Dark Pulsar in CTA 1 Credit: NASA, S. Pineault (DRAO) Explanation: Where's the pulsar? Previously, the nebula CTA 1 showed an expanding supernova remnant, a jet, and a point source expected to be a pulsar -- a rotating neutron star producing pulses at radio energies. But no radio pulses were detected. Now NASA's recently deployed Fermi Space Telescope has solved the mystery with some of its initial observations indicating that the point source is pulsing at gamma-ray energies. The strange source is the first of a class that might be dubbed "dark pulsars", rotating neutron stars that appear to pulse only in high-energy radiations. Such pulsars might not be detectable in radio or visible light if they emit those radiations into a narrow beam not seen from Earth. If true, our Galaxy might have more pulsars left for Fermi to discover. Studying the gamma-ray properties of pulsars gives valuable clues to physics of the emission regions on neutron stars. In this graphic, the pulsar's position is indicated in the wider CTA 1 supernova remnant. An artist's illustration of the pulsar beaming at gamma-ray energies is shown in the inset. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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Beautiful Spiral NGC 7331 Credit & Copyright: Vicent Peris (OAUV / PTeam), Gilles Bergond, Calar Alto Observatory. Explanation: A favorite target for astronomers, big, beautiful spiral galaxy NGC 7331 is one of the brighter galaxies not found in Charles Messier's famous 18th century catalog. About 50 million light-years distant in the northern constellation Pegasus and similar in size to our own Milky Way Galaxy, NGC 7331 is often imaged as the foreground of a visual grouping that includes an intriguing assortment of background galaxies some ten times farther away. This striking image of the well-studied island universe and environs was produced using data from the Calar Alto Observatory in southern Spain. Perhaps the deepest view of the region yet, the image data were processed to reveal sharp details of all sizes in both bright and faint areas. A color balance was chosen so that white would be the result of averaging colors over the entire galaxy. The result shows off a wealth of remarkable features in NGC 7331 and its surroundings. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Great Orion Nebulae Credit & Copyright: Tony Hallas Explanation: The Great Nebula in Orion, also known as M42, is one of the most famous nebulae in the sky. The star forming region's glowing gas clouds and hot young stars are on the right in this sharp and colorful two frame mosaic that includes the smaller nebula M43 near center and dusty, bluish reflection nebulae NGC 1977 and friends on the left. Located at the edge of an otherwise invisible giant molecular cloud complex, these eye-catching nebulae represent only a small fraction of this galactic neighborhood's wealth of interstellar material. Within the well-studied stellar nursery, astronomers have also identified what appear to be numerous infant solar systems. The gorgeous skyscape spans nearly two degrees or about 45 light-years at the Orion Nebula's estimated distance of 1,500 light-years. Editor's Note: A version of the image with labels generated by Astrometry.net is available here. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
#690
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Συνδεδεμένοι χρήστες που διαβάζουν αυτό το θέμα: 3 (0 μέλη και 3 επισκέπτες) | |
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