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موضوع: Astronomical News

  1. Top | #1
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    Post Astronomical News

    Hello.
    I want to put this post to talk about latest news around astronomy, Its a new astronomical news page......
    I'll appreciate if u help me with this post........


    Thank u All
    ویرایش توسط planetstruck : 04-11-2011 در ساعت 09:36 AM دلیل: Adding words,Correcting Grammar points


  2. Top | #31
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          Two planets found sharing one orbit

    Buried in the flood of data from the Kepler telescope is a planetary system unlike any seen before. Two of its apparent planets share the same orbit around their star. If the discovery is confirmed, it would bolster a theory that Earth once shared its orbit with a Mars-sized body that later crashed into it, resulting in the moon's formation




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  4. Top | #32
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    Awe-struck astronaut captures Endeavour in dramatic silhouette against Earth's horizon
    By DAILY MAIL REPORTER
    16th February 2010


    More than 200miles above Earth, the space shuttle Endeavour can be seen silhouetted against our planet's colourful horizon
    The image was taken by a member of the Expedition 22 crew on board the International Space Station as the shuttle approached for docking last Tuesday
    The tricky manoeuvre was performed while both the shuttle and station were travelling at more than 17,000mph
    Shadow of the Earth: The silhouette of the space shuttle Endeavour above our planet


    The International Space Station backdropped by Earth's horizon and the blackness of space


    امضای ایشان
    !Always be a first-rate version of yourself, instead of a second-rate version of somebody else


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  6. Top | #33
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    Endeavour astronaut Stephen Robinson was awe-struck as the shuttle approached the station
    'To look up and see what humankind could really accomplish in space was just almost impossible to believe. It seemed like science fiction"he said
    'Now here we are with human beings that are living on board. That truly is the amazing legacy of the space shuttle programme
    The shuttle has delivered vital food supplies and air cleaning equipment to the station as well as a new observation deck


    Nasa astronaut T.J. Creamer & Jeffrey Williams with fresh produce brought by the shuttle



    The International Space Station is seen leaving Earth in this photo taken from the Intracoastal Waterway Bridge, in Ponte Vedra, Florida
    ویرایش توسط planetstruck : 02-26-2011 در ساعت 04:31 PM دلیل: removing
    امضای ایشان
    !Always be a first-rate version of yourself, instead of a second-rate version of somebody else


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  8. Top | #34
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          This is your chance to go to Mars


    Be come a part of history


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  10. Top | #35
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          Geyser moon puts its mark on Saturn

    Geyser moon puts its mark on Saturn


    18:00 20 April 2011 by David Shiga
    For similar stories, visit the Solar System and Saturn and its moons Topic Guides

    An electrical current is flowing from Saturn's moon Enceladus to the ringed planet, creating a glowing patch in the planet's atmosphere.

    Ultraviolet images taken by the Cassini spacecraft revealed the patch, which is distinct from the planet's auroras. It lies near Saturn's north pole – exactly where electrons emitted by Enceladus would hit after being chanelled along the planet's magnetic field lines, report Wayne Pryor of Central Arizona College in Coolidge and colleagues.
    Where do the electrons come from? The team believes that sunlight knocks them off water molecules spewed by geysers at Enceladus's south pole.
    The brightness of the patch varies, which could be due to variations in the amount of water vapour released by Enceladus, says the team.

    Journal reference: Nature, DOI: 10.1038/nature09928
    تصاویر کوچک فایل پیوست تصاویر کوچک فایل پیوست Astronomical News-dn20399-2_300-jpg  
    امضای ایشان
    برگ در انتهاي زوال مي افتد و ميوه در ابتداي کمال … بنگر که چگونه مي افتي ؟!

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  12. Top | #36
    کاربر فعال

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    NASA Twitter Followers Will Fly Shuttle Simulator During Tweetup At Johnson Space Center

    HOUSTON -- So you think you can pilot the space shuttle? NASA will give 30 of its Twitter followers a chance to test their skills at space shuttle ascent, rendezvous or landing aboard the same simulator astronauts use to train for their missions.

    NASA's Johnson Space Center is hosting a daylong Tweetup on July 19, during space shuttle Atlantis' STS-135 mission to the International Space Station. Participants will get a behind-the-scenes tour at Johnson and a hands-on opportunity aboard the shuttle simulator to take control in a training scenario. The tour includes a look at the Mission Control Center and astronauts' training facilities. Visitors also will have the opportunity to speak with flight directors, trainers, astronauts and managers.

    Atlantis is targeted to launch from NASA's Kennedy Space Center in Florida at 10:26 a.m. CDT on July 8. If it launches as planned, the Tweetup will take place one day before the last orbiter of the shuttle fleet makes its final landing.

    Tweetup registration opens at 11 a.m. on Tuesday, June 28, and closes 24 hours later at 11 a.m. on Wednesday, June 29. NASA will select 30 individuals randomly from the online registrants.

    Reporters are invited to cover the Tweetup from 8 a.m. to 5 p.m. Media representatives planning to attend should contact Tammie Letroise-Brown at 281-483-4942.
    ویرایش توسط planetstruck : 06-28-2011 در ساعت 01:04 PM دلیل: arranging

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  14. Top | #37
    کاربر فعال

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    What's to Blame for Wild Weather? "La Nada"

    Such sheets of fire, such bursts of horrid thunder,
    Such groans of roaring wind and rain, I never
    Remember to have heard; man's nature cannot carry
    The affliction nor the fear
    … from Shakespeare's Tragedy of King Lear

    June 21, 2011: Record snowfall, killer tornadoes, devastating floods: There’s no doubt about it. Since Dec. 2010, the weather in the USA has been positively wild. But why?
    Some recent news reports have attributed the phenomenon to an extreme "La Niña," a band of cold water stretching across the Pacific Ocean with global repercussions for climate and weather. But NASA climatologist Bill Patzert names a different suspect: "La Nada."
    "La Niña was strong in December," he says. "But back in January it pulled a disappearing act and left us with nothing – La Nada – to constrain the jet stream. Like an unruly teenager, the jet stream took advantage of the newfound freedom--and the results were disastrous."
    La Niña and El Niño are opposite extremes of a great Pacific oscillation. Every 2 to 7 years, surface waters across the equatorial Pacific warm up (El Niño) and then they cool down again (La Niña). Each condition has its own distinct effects on weather.

    The blue and purple band in this satellite image of the Pacific Ocean traces the cool waters of the La Niña phenomenon in December 2010. (from Ocean Surface Topography Mission (OSTM)/Jason-2 satellite, Credit: NASA JPL)

    The winter of 2010 began with La Niña conditions taking hold. A "normal" La Niña would have pushed the jet stream northward, pushing cold arctic air (one of the ingredients of severe weather) away from the lower US. But this La Niña petered out quickly, and no El Niño rose up to replace it. The jet stream was free to misbehave.

    "By mid-January 2011, La Niña weakened rapidly and by mid-February it was 'adios La Niña,' allowing the jet stream to meander wildly around the US. Consequently the weather pattern became dominated by strong outbreaks of frigid polar air, producing blizzards across the West, Upper Midwest, and northeast US."1
    The situation lingered into spring -- and things got ugly. Russell Schneider, Director of the NOAA-NWS Storm Prediction Center, explains:
    "First, very strong winds out of the south carrying warm, moist air from the Gulf of Mexico met cold jet stream winds racing in from the west. Stacking these two air masses on top of each other created the degree of instability that fuels intense thunderstorms."
    Extreme contrasts in wind speeds and directions of the upper and lower atmosphere transformed ordinary thunderstorms into long-lived rotating supercells capable of producing violent tornadoes.2
    In Patzert's words, "The jet stream -- on steroids -- acted as an atmospheric mix master, causing tornadoes to explode across Dixie and Tornado Alleys, and even into Massachusetts."

    This satellite image, taken in April 2011, reveals La Niña's rapid exit from the equator near the US coast. The cool (false-color blue) water was gone by early spring. (from Ocean Surface Topography Mission (OSTM)/Jason-2 satellite, Credit: NASA JPL)

    All this because of a flaky La Niña?
    "La Niña and El Niño affect the atmosphere's energy balance because they determine the location of warm water in the Pacific, and that in turn determines where huge clusters of tropical thunderstorms form," explains Schneider. "These storms are the main energy source from the tropics influencing the large scale pattern of the jet stream that flows through the US."
    In agreement with Patzert, he notes that the very strong and active jet stream across the lower US in April "may have been related to the weakening La Niña conditions observed over the tropical Pacific."
    And of course there's this million dollar question: "Does any research point to climate change as a cause of this wild weather?"
    "Global warming is certainly happening," asserts Patzert, "but we can't discount global warming or blame it for the 2011 tornado season. We just don't know ... Yet."3
    What will happen next? And please don't say, "La Nada."
    Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA
    End Notes(1) Other atmospheric factors also contributed to the inflow of frigid polar air, says Patzert. One of the most significant was a weakening in the whirlpool motion of the air around the North Pole. As a result of this weakening, more cold air flowed away from the pole and down toward the states. Climatologists call this an "arctic oscillation."
    (2) Imagine a paddle wheel oriented like a Ferris wheel and placed in winds that that are much stronger at the top than at the bottom. The wheel will spin in the direction of the strong winds above. This spring, these strong, turning winds led to ongoing rotation of the supercells themselves. So we ended up with intense rotation and updraft close to Earth's surface -- conditions ripe for strong tornadoes.
    (3) On May 26, 2011, Patzert posted a comment about this topic on Andrew Revkin’s The New York Times' DOT EARTH Blog, "Demography, Design, Atom Bombs and Tornado Deaths."
    ویرایش توسط planetstruck : 06-28-2011 در ساعت 01:53 PM دلیل: Arranging

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  16. Top | #38
    کاربر فعال

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    Free-Floating Planets May Be More Common Than Stars

    May 18, 2011: Astronomers have discovered a new class of Jupiter-sized planets floating alone in the dark of space, away from the light of a star. The team believes these lone worlds are probably outcasts from developing planetary systems and, moreover, they could be twice as numerous as the stars themselves.
    "Although free-floating planets have been predicted, they finally have been detected," said Mario Perez, exoplanet program scientist at NASA Headquarters in Washington. "[This has] major implications for models of planetary formation and evolution."
    The discovery is based on a joint Japan-New Zealand survey that scanned the center of the Milky Way galaxy during 2006 and 2007, revealing evidence for up to 10 free-floating planets roughly the mass of Jupiter. The isolated orbs, also known as orphan planets, are difficult to spot, and had gone undetected until now. The planets are located at an average approximate distance of 10,000 to 20,000 light years from Earth.

    This artist's concept illustrates a Jupiter-like planet alone in the dark of space, floating freely without a parent star. [larger image] [video]

    This could be just the tip of the iceberg. The team estimates there are about twice as many free-floating Jupiter-mass planets as stars. In addition, these worlds are thought to be at least as common as planets that orbit stars. This adds up to hundreds of billions of lone planets in our Milky Way galaxy alone.
    "Our survey is like a population census," said David Bennett, a NASA and National Science Foundation-funded co-author of the study from the University of Notre Dame in South Bend, Ind. "We sampled a portion of the galaxy, and based on these data, can estimate overall numbers in the galaxy."
    The study, led by Takahiro Sumi from Osaka University in Japan, appears in the May 19 issue of the journal Nature. The survey is not sensitive to planets smaller than Jupiter and Saturn, but theories suggest lower-mass planets like Earth should be ejected from their stars more often. As a result, they are thought to be more common than free-floating Jupiters.
    Previous observations spotted a handful of free-floating planet-like objects within star-forming clusters, with masses three times that of Jupiter. But scientists suspect the gaseous bodies form more like stars than planets. These small, dim orbs, called brown dwarfs, grow from collapsing balls of gas and dust, but lack the mass to ignite their nuclear fuel and shine with starlight. It is thought the smallest brown dwarfs are approximately the size of large planets.

    A video from JPL describes the microlensing technique astronomers used to detect the orphan planets.

    On the other hand, it is likely that some planets are ejected from their early, turbulent solar systems, due to close gravitational encounters with other planets or stars. Without a star to circle, these planets would move through the galaxy as our sun and others stars do, in stable orbits around the galaxy's center. The discovery of 10 free-floating Jupiters supports the ejection scenario, though it's possible both mechanisms are at play.
    "If free-floating planets formed like stars, then we would have expected to see only one or two of them in our survey instead of 10," Bennett said. "Our results suggest that planetary systems often become unstable, with planets being kicked out from their places of birth."
    The observations cannot rule out the possibility that some of these planets may be in orbit around distant stars, but other research indicates Jupiter-mass planets in such distant orbits are rare.
    The survey, the Microlensing Observations in Astrophysics (MOA), is named in part after a giant wingless, extinct bird family from New Zealand called the moa. A 5.9-foot (1.8-meter) telescope at Mount John University Observatory in New Zealand is used to regularly scan the copious stars at the center of our galaxy for gravitational microlensing events. These occur when something, such as a star or planet, passes in front of another more distant star. The passing body's gravity warps the light of the background star, causing it to magnify and brighten. Heftier passing bodies, like massive stars, will warp the light of the background star to a greater extent,resulting in brightening events that can last weeks. Small planet-size bodies will cause less of a distortion, and brighten a star for only a few days or less.
    A second microlensing survey group, the Optical Gravitational Lensing Experiment (OGLE), contributed to this discovery using a 4.2-foot (1.3 meter) telescope in Chile. The OGLE group also observed many of the same events, and their observations independently confirmed the analysis of the MOA group.

    From:http://www.nasa.gov/topics/universe/
    ویرایش توسط planetstruck : 06-28-2011 در ساعت 01:27 PM دلیل: Arranging, putting refrences

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  18. Top | #39
    کاربر ممتاز

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    نقل قول نوشته اصلی توسط گلناز نمایش پست ها
    NASA Twitter Followers Will Fly Shuttle Simulator During Tweetup At Johnson Space Center
    .................................................. ..................... and so on


    Hi dear Golnaz!
    thank u 4 ur News.
    please put the refrences of that news
    I couldn't find it my self in due to put it here

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  20. Top | #40
    کاربر فعال

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          NASA Will Host 150 People For Tweetup At Launch Of Jupiter-Bound Mission

    Astronomical News         
    WASHINGTON -- NASA will host a two-day launch Tweetup for 150 of its Twitter followers on Aug. 4 - 5 at the agency's Kennedy Space Center in Florida. The Tweetup is expected to culminate in the launch of the Jupiter-bound Juno spacecraft aboard an Atlas V rocket.

    The launch window opens at 11:39 a.m. EDT on Aug. 5. The spacecraft is expected to arrive at Jupiter in 2016. The mission will investigate the gas giant's origins, structure, atmosphere and magnetosphere. Juno's color camera will provide close-up images of Jupiter, including the first detailed glimpse of the planet's poles.

    The Tweetup will provide @NASA Twitter followers with the opportunity to tour the Kennedy Space Center Visitor Complex; speak with scientists and engineers from the Juno and other upcoming missions; and, if all goes as scheduled, view the spacecraft launch. The event also will provide participants the opportunity to meet fellow tweeps and members of NASA's social media team.

    Juno is the second of four space missions launching this year, making 2011 one of the busiest ever in planetary exploration. Aquarius was launched June 10 to study ocean salinity; Grail will launch Sept. 8 to study the moon's gravity field; and the Mars Science Laboratory/Curiosity rover heads to the Red Planet no earlier than Nov. 25.
    ویرایش توسط planetstruck : 06-29-2011 در ساعت 10:11 AM دلیل: arranging

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