Tag: Science

  • Free Falling

    Published in 1869, Edward Everett Hale’s story “The Brick Moon” described the launch of an artificial satellite nearly a century before Sputnik:

    If from the surface of the earth, by a gigantic peashooter, you could shoot a pea upward from Greenwich, aimed northward as well as upward; if you drove it so fast and far that when its power of ascent was exhausted, and it began to fall, it should clear the earth, and pass outside the North Pole; if you had given it sufficient power to get it half round the earth without touching, that pea would clear the earth forever. It would continue to rotate above the North Pole, above the Feejee Island place, above the South Pole and Greenwich, forever, with the impulse with which it had first cleared our atmosphere and attraction. If only we could see that pea as it revolved in that convenient orbit, then we could measure the longitude from that, as soon as we knew how high the orbit was, as well as if it were the ring of Saturn.

    Because the 200-foot brick sphere is accidentally launched with human occupants, Hale perhaps also deserves credit for anticipating the space station.

    Posted via web from Monicks: Unleashed

  • As the Sun Awakens, NASA Keeps a Wary Eye on Space Weather

    Earth and space are about to come into contact in a way that’s new to human history. To make preparations, authorities in Washington DC are holding a meeting: The Space Weather Enterprise Forum at the National Press Club on June 8th.

    Many technologies of the 21st century are vulnerable to solar storms. Credit: NASA

    Richard Fisher, head of NASA’s Heliophysics Division, explains what it’s all about:

    “The sun is waking up from a deep slumber, and in the next few years we expect to see much higher levels of solar activity. At the same time, our technological society has developed an unprecedented sensitivity to solar storms. The intersection of these two issues is what we’re getting together to discuss.”

    The National Academy of Sciences framed the problem two years ago in a landmark report entitled “Severe Space Weather Events—Societal and Economic Impacts.” It noted how people of the 21st-century rely on high-tech systems for the basics of daily life. Smart power grids, GPS navigation, air travel, financial services and emergency radio communications can all be knocked out by intense solar activity. A century-class solar storm, the Academy warned, could cause twenty times more economic damage than Hurricane Katrina.

    Much of the damage can be mitigated if managers know a storm is coming. Putting satellites in ’safe mode’ and disconnecting transformers can protect these assets from damaging electrical surges. Preventative action, however, requires accurate forecasting—a job that has been assigned to NOAA.

    “Space weather forecasting is still in its infancy, but we’re making rapid progress,” says Thomas Bogdan, director of NOAA’s Space Weather Prediction Center in Boulder, Colorado.

    Bogdan sees the collaboration between NASA and NOAA as key. “NASA’s fleet of heliophysics research spacecraft provides us with up-to-the-minute information about what’s happening on the sun. They are an important complement to our own GOES and POES satellites, which focus more on the near-Earth environment.”

    [youtube=http://www.youtube.com/watch?v=Ctjb-f75PkY]

    Among dozens of NASA spacecraft, he notes three of special significance: STEREO, SDO and ACE.

    STEREO (Solar Terrestrial Relations Observatory) is a pair of spacecraft stationed on opposite sides of the sun with a combined view of 90% of the stellar surface. In the past, active sunspots could hide out on the sun’s farside, invisible from Earth, and then suddenly emerge over the limb spitting flares and CMEs. STEREO makes such surprise attacks impossible.

    SDO (the Solar Dynamics Observatory) is the newest addition to NASA’s fleet. Just launched in February, it is able to photograph solar active regions with unprecedented spectral, temporal and spatial resolution. Researchers can now study eruptions in exquisite detail, raising hopes that they will learn how flares work and how to predict them. SDO also monitors the sun’s extreme UV output, which controls the response of Earth’s atmosphere to solar variability.

    Bogdan’s favorite NASA satellite, however, is an old one: the Advanced Composition Explorer (ACE) launched in 1997. “Where would we be without it?” he wonders. ACE is a solar wind monitor. It sits upstream between the sun and Earth, detecting solar wind gusts, billion-ton CMEs, and radiation storms as much as 30 minutes before they hit our planet.

    “ACE is our best early warning system,” says Bogdan. “It allows us to notify utility and satellite operators when a storm is about to hit.”

    NASA spacecraft were not originally intended for operational forecasting—”but it turns out that our data have practical economic and civil uses,” notes Fisher. “This is a good example of space science supporting modern society.”

    2010 marks the 4th year in a row that policymakers, researchers, legislators and reporters have gathered in Washington DC to share ideas about space weather. This year, forum organizers plan to sharpen the focus on critical infrastructure protection. The ultimate goal is to improve the nation’s ability to prepare, mitigate, and respond to potentially devastating space weather events.

    “I believe we’re on the threshold of a new era in which space weather can be as influential in our daily lives as ordinary terrestrial weather.” Fisher concludes. “We take this very seriously indeed.”

  • Astrophotography | Comet C/2009 R1 (McNaught) in Andromeda

    Comet C/2009 R1 (McNaught) in Andromeda
    Image Details Imaging Details
    Comet: 
    C/2009 R1 (McNaught)

    Discoverer: 
    Robert McNaught 
    Sep 09, 2009

    Type: 
    Hyperbolic

    Period: 
    N/A

    Constellation: 
    Andromeda

    RA / Dec: 
    02h 21m 36s / 
    42° 05′ 32″

    Distance: 
    175.1 million km

    Magnitude: 
    5.0 – 6.0

    Date: 
    June 8, 2010 
    03:15 – 04:07 UT+3

    Location: 
    Athens, Greece 
    (38.2997° N, 23.7430° E)

    Equipment: 
    AP 160/f7.5 StarFire EDF
    AP 1200GTO GEM 
    SBIG ST-10XME 
    SBIG CFW10 
    SBIG LRGB filters

    Integrations:

    Lum :  10 min (10 x 1 min)
    Red :  10 min (10 x 1 min)
    Green :  10 min (10 x 1 min)
    Blue :  10 min (10 x 1 min)
    Binning :  1×1 (Lum), 1×1 (RGB)

    Image Scale: 
    1.17″ / pixel

    Temperatures:

    Ambient : + 19.0 ° C
    CCD Chip : – 17.5 ° C

    Software: 
    CCDSoft V5.00.195
    CCDStack V1.6.0.5
    Photoshop CS2

    These travelling masses of ice and dust galloping throughout the universe are believed to have shaped the course of life on this planet. As a result of comet-hunting, many deep-sky objects including nebulae and galaxies have been discovered with perhaps the most obvious collection being the 109 (or 110) DSO’s attributed to Charles Messier. With over 1000 comets now having been catalogued and approximately 200 having been established as being periodic, historical records suggest comets to have been observed and documented as far back as 240 BC (Comet Halley by the Chinese).

    Comets are appealing to amateurs for a variety of reasons: they lead to incredible photographs thanks to their glowing and colourful tails extending millions of kilometers as they approach the sun and the ice and various frozen gases in the nucleus begin to vaporize; they are the precursors of meteor showers as remnants left behind on prior visits are encountered by our planet while we orbit the sun; and they represent an active adventure and form the basis of a “culture” (comet hunters) based on the discovery of new comets during the early dawn hours on the eastern horizon or just after sunset on the western horizon.

    Note: Comet C/2009 R1 (McNaught) illustrated below while passing through the constellation of Andromenda and within the immediate vicinity of the edge-on galaxy NGC 891 was discovered on Sept 9, 2009 by Siding Spring Observatory astronomer Robert McNaught in five plates and was estimated to be magnitude 17.3 to 17.5. Continuous monitoring has revealed a continuing brightening of the nucleus and which is now expected to reach mag 2 by the end of June and early parts of July when it will finally be lost in the morning twilight. Perihelion has been estimated to be July 2, 2010.

    For an ephemeris and orbital elements on this hyperbolic comet from Harvard’s Minor Planet Center, click here. For a simulation of the comet including various orbital elements and physical parameters, click here.

    Note: The comet was only 12 to 19 degrees above the horizon during the imaging session!

     

    via perseus.gr

     

     

    Posted via web from Monicks: Unleashed