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Εργαλεία Θεμάτων | Τρόποι εμφάνισης |
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#1591
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![]() Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση NGC 1499: The California Nebula Credit & Copyright: Markus Noller (Deep Sky Images) Explanation: What's California doing in space? Drifting through the Orion Arm of the spiral Milky Way Galaxy, this cosmic cloud by chance echoes the outline of California on the west coast of the United States. Our own Sun also lies within the Milky Way's Orion Arm, only about 1,500 light-years from the California Nebula. Also known as NGC 1499, the classic emission nebula is around 100 light-years long. On many images, the most prominent glow of the California Nebula is the red light characteristic of hydrogen atoms recombining with long lost electrons, stripped away (ionized) by energetic starlight. In the above image, however, hydrogen is colored green, while silicon is mapped to red and oxygen mapped to blue. The star most likely providing the energetic starlight that ionizes much of the nebular gas is the bright, hot, bluish Xi Persei, just outside the right image edge. A regular target for astrophotographers, the California Nebula can be spotted with a wide-field telescope under a dark sky toward the constellation of Perseus, not far from the Pleiades. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (14-03-11) |
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#1592
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![]() Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Lunar Nearside Credit: NASA / GSFC / Arizona State Univ. / Lunar Reconnaissance Orbiter Explanation: About 1,300 images from the Lunar Reconnaissance Orbiter spacecraft's wide angle camera were used to compose this spectacular view of a familiar face - the lunar nearside. But why is there a lunar nearside? The Moon rotates on its axis and orbits the Earth at the same rate, about once every 28 days. Tidally locked in this configuration, the synchronous rotation always keeps one side, the nearside, facing Earth. As a result, featured in remarkable detail in the full resolution mosaic, the smooth, dark, lunar mare (actually lava-flooded impact basins), and rugged highlands, are well-known to earthbound skygazers. To find your favorite mare or large crater, just slide your cursor over the picture. The LRO images used to construct the mosaic were recorded over a two week period last December. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (03-03-11) |
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#1593
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![]() Cooling Neutron Star Credit: X-ray: NASA / CXC / UNAM / Ioffe / D.Page, P.Shternin et al; Optical: NASA / STScI; Illustration: NASA/CXC/M.Weiss) Explanation: Supernova remnant Cassiopeia A (Cass A) is a comfortable 11,000 light-years away. Light from the Cass A supernova, the death explosion of a massive star, first reached Earth just 330 years ago. The expanding debris cloud spans about 15 light-years in this composite X-ray/optical image, while the bright source near the center is a neutron star (inset illustration) the incredibly dense, collapsed remains of the stellar core. Still hot enough to emit X-rays, Cass A's neutron star is cooling. In fact, 10 years of observations with the orbiting Chandra X-ray observatory find that the neutron star is cooling rapidly, so rapidly that researchers suspect a large part of the neutron star's core is forming a frictionless neutron superfluid. The Chandra results represent the first observational evidence for this bizarre state of matter. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (05-03-11) |
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#1594
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![]() Asteroids in the Distance Credit: R. Evans & K. Stapelfeldt (JPL), WFPC2, HST, NASA Explanation: Rocks from space hit Earth every day. The larger the rock, though, the less often Earth is struck. Many kilograms of space dust pitter to Earth daily. Larger bits appear initially as a bright meteor. Baseball-sized rocks and ice-balls streak through our atmosphere daily, most evaporating quickly to nothing. Significant threats do exist for rocks near 100 meters in diameter, which strike the Earth roughly every 1000 years. An object this size could cause significant tsunamis were it to strike an ocean, potentially devastating even distant shores. A collision with a massive asteroid, over 1 km across, is more rare, occurring typically millions of years apart, but could have truly global consequences. Many asteroids remain undiscovered. In fact, one was discovered in 1998 as the long blue streak in the above archival image taken by the Hubble Space Telescope. In 2002 June, the small 100-meter asteroid 2002 MN was discovered only after it whizzed by the Earth, passing well within the orbit of the Moon. 2002 MN passed closer than any asteroid since 1994 XM1, but not as close as 2004 MN4 will pass in 2029. A collision with a large asteroid would not affect Earth's orbit so much as raise dust that would affect Earth's climate. One likely result is a global extinction of many species of life, possibly dwarfing the ongoing extinction occurring now. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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#1595
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A Solar Prominence Eruption from SDO Credit: NASA/Goddard/SDO AIA Team Explanation: One of the most spectacular solar sights is an erupting prominence. Two weeks ago, NASA's Sun-orbiting Solar Dynamic Observatory spacecraft imaged an impressively large prominence erupting from the surface. The dramatic explosion was captured in ultraviolet light in the above time lapse video covering 90 minutes, where a new frame was taken every 24 seconds. The scale of the prominence is huge -- the entire Earth would easily fit under the flowing curtain of hot gas. A solar prominence is channeled and sometimes held above the Sun's surface by the Sun's magnetic field. A quiescent prominence typically lasts about a month, and may erupt in a Coronal Mass Ejection (CME) expelling hot gas into the Solar System. The energy mechanism that creates a solar prominence is still a topic of research. As the Sun progresses toward Solar Maximum in the next few years, solar activity like eruptive prominences are expected to become more common. Πηγή Σχόλιο : Η εικόνα είναι απίστευτη. Μου κόβεται η αναπνοή, όταν συλλογίζομαι ότι αυτές οι «φλογίτσες», μπορεί να είναι σαν το μέγεθος της Γης...
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (07-03-11) |
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#1596
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![]() ![]() Διευκρίνιση: Η Γη δεν είναι τόσο κοντά στον Ήλιο.
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may you live in interesting times |
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#1597
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![]() Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση The International Space Station Expands Again Credit: STS-133 Shuttle Crew, NASA Explanation: The developing International Space Station (ISS) has changed its appearance again. In a recently completed rendezvous, the Space Shuttle orbiter Discovery, in its final flight, visited the ISS and added components that included the Leonardo Multi Purpose Logistics Module. The ISS and many of its modules and expansive solar panels are visible in the above picture taken by the Discovery Crew after leaving the ISS to return to Earth. The world's foremost space outpost can be seen developing over the past several years by comparing the above image to other past images. Also visible above are many different types of modules and supply ships. Construction began on the ISS in 1998. Πηγή Σχόλιο : Θαυμάστε αυτό το μεγάλο έργο της ανθρώπινης επινόησης. Την, επιτέλους, αγαστή συνεργασία πολλών εθνών, για έναν κοινό σκοπό, την εξερεύνηση του διαστήματος. Οι νέοι Βάσκο Ντε Γκάμα, Μαγγελάνος, Ντιάζ και Κολόμβος
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (09-03-11) |
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#1598
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![]() Discovery in Twilight Image Credit & Copyright: Tamas Ladanyi (TWAN) Explanation: As evening twilight faded on March 7, sky gazers around planet Earth enjoyed a beautiful pairing of young crescent Moon and brilliant planet Jupiter. Along with stars setting in the west, the two bright celestial beacons, Moon above and Jupiter below, leave short trails in this well-planned time exposure, a composite of 54 individual frames each 4 seconds long. On its final flight, the Space Shuttle Discovery and International Space Station form the second close pairing in the night skyscape. Still glinting in the sunlight in low Earth orbit, they gracefully trace overlapping arcs from lower right to upper left. Moon, Jupiter, Discovery, and ISS are reflected in the calm waters of Lake Bakonybél, Hungary. Want to see the sequence of frames as a short youtube video? Check it out here. In the video, the trails of the ISS and Discovery are seen to separate as the pair passes above the Moon. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (10-03-11) |
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#1599
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![]() Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση AE Aurigae and the Flaming Star Nebula Image Credit & Copyright: Rolf Geissinger Explanation: AE Aurigae is the bright star below and left of center in this evocative portrait of IC 405, also known as the Flaming Star Nebula. Embedded in the cosmic cloud, the hot, variable O-type star energizes the glow of hydrogen along convoluted filaments of atomic gas, its blue starlight scattered by interstellar dust. But AE Aurigae wasn't formed in the nebula it illuminates. Retracing the star's motion through space, astronomers conclude that AE Aurigae was probably born in the Orion Nebula. Close gravitational encounters with other stars ejected it from the region, along with another O star, Mu Columbae, over two million years ago. The runaway stars have drifted in opposite directions ever since, separating at about 200 kilometers per second. This sharp, detailed image of IC 405 spans over 5 light-years at the nebula's estimated distance of 1,500 light-years in the northern constellation Auriga, the Charioteer. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (11-03-11) |
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#1600
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![]() Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Mare Orientale Credit: NASA / GSFC / Arizona State Univ. / Lunar Reconnaissance Orbiter Explanation: Shaped like a target ring bull's-eye, the Mare Orientale is one of the most striking large scale lunar features. Located on the Moon's extreme western edge, it is unfortunately difficult to see from an earthbound perspective. Still, this mosaic of the multi-ring impact basin, the youngest of the large lunar basins shows off intriguing details (full resolution mosaic), based on Wide Angle Camera images from the Lunar Reconnaissance Orbiter. Only partially flooded by lava the Mare Orientale is over 3 billion years old, about 600 miles (950 kilometers) across and was formed by the impact of an asteroid sized object. The collision caused ripples in the lunar crust resulting in the concentric circular features. Though it may seem a little ironic to denizens of the space age who recognize the Moon as a dry and airless world, a dark, smooth lunar region is called a mare (plural maria), latin for sea, because astronomers once thought such regions might actually be seas. Πηγή Σχόλιο : Απίστευτος ο κυματισμός !!! Είναι αυτό που λέμε «σου ήρθε ο ουρανός σφοντύλι».
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (12-03-11) |
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#1601
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![]() Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση A Mars Panorama from the Phoenix Lander Credit: Phoenix Mission Team, NASA, JPL-Caltech, U. Arizona Explanation: If you could stand on Mars, what would you see? The robotic Phoenix spacecraft that landed on Mars in 2008 recorded the above spectacular panorama. The above image is actually a digital combination of over 100 camera pointings and surveys fully 360 degrees around the busy robotic laboratory. Scrolling right will reveal the rest of the panoramic image. Visible in the image foreground are circular solar panels, various Phoenix instruments, rust colored rocks, a trench dug by Phoenix to probe Mars' chemical composition, a vast plateau of dirt and dirt-covered ice, and, far in the distance, the dust colored atmosphere of Mars. Phoenix landed in the far north of Mars and has used its sophisticated laboratory to search for signs that past life might have been possible. Soil analyses have confirmed the presence of ice and gave unexpected indications of perchlorate salts. Whether Martian life could have evolved around such perchlorates is an ongoing topic of research. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
Οι παρακάτω χρήστες έχουν πει 'Ευχαριστώ' στον/στην Xenios για αυτό το μήνυμα: | ||
jimil (14-03-11) |
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#1602
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![]() Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση Spacecrafts Streak Over Colorado Credit & Copyright: Robert Arn Explanation: Have you ever seen a "star" drifting slowly overhead, but not known what it was? Sometimes even pointing it out to friends or family will only lead to a shrug. What you are seeing, most likely, is a spacecraft in low Earth orbit reflecting back sunlight as it circles the Earth once every 90 minutes or so. Two of the brighter spacecraft in the present day sky are the International Space Station (ISS), and, when it is up, a NASA space shuttle. As relative orientations change, the brightness of reflections may also change, sometimes suddenly. Another source of bright drifting objects, Iridium communication satellites, may even appear to flare up to become brighter than any other sky object for a few seconds. Pictured above, two bright points of light separated by only a few degrees drifted together across the sky above Lory State Park, Colorado, USA last week, just after sunset. These lights were were the ISS and the space shuttle Discovery, which had undocked from the ISS a few hours earlier. Given a digital fusion of many separate camera exposures and a wide angle perspective, the pair appears above as steaks in front of point-like stars. Web sites now exist that can help you identify unknown "drifters" and even predict the time of the next pass of the ISS visible from your location. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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#1603
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Cassini Approaches Saturn Credit & Copyright: Cassini Imaging Team, ISS, JPL, ESA, NASA, S. Van Vuuren et al.; Music: Adagio for Strings (NY Philharmonic) Explanation: What would it look like to approach Saturn in a spaceship? One doesn't have to just imagine -- the Cassini spacecraft did just this in 2004, recording thousands of images along the way, and thousands more since entering orbit. Recently, some of these images have been digitally tweaked, cropped, and compiled into the above inspiring video which is part of a larger developing IMAX movie project named Outside In. In the last sequence, Saturn looms increasingly large on approach as cloudy Titan swoops below. With Saturn whirling around in the background, Cassini is next depicted flying over Mimas, with large Herschel Crater clearly visible. Saturn's majestic rings then take over the show as Cassini crosses Saturn's thin ring plane. Dark shadows of the ring appear on Saturn itself. Finally, the enigmatic ice-geyser moon Enceladus appears in the distance and then is approached just as the video clip ends. Πηγή
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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#1604
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#1605
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Να πω την αλήθεια το πρωί δεν είδα όλο το video.
Έχω κυριολεκτικά πάθει πλάκα, είναι τόσο εντυπωσιακό που σου κόβει την ανάσα. Ότι πιο όμορφο είδαμε από το Cassini.
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όταν γράφεται η ιστορία της ζωής σου, μην αφήνεις κανέναν να κρατάει την πένα |
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Συνδεδεμένοι χρήστες που διαβάζουν αυτό το θέμα: 3 (0 μέλη και 3 επισκέπτες) | |
Εργαλεία Θεμάτων | |
Τρόποι εμφάνισης | |
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