The MDL Times - Science and Tech. News on MDL

Discussion in 'Serious Discussion' started by kldpdas, Jun 30, 2011.

  1. R29k

    R29k MDL GLaDOS

    Feb 13, 2011
    5,171
    4,811
    180
    The universe may have been born spinning, according to new findings ....

    Source
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  2. R29k

    R29k MDL GLaDOS

    Feb 13, 2011
    5,171
    4,811
    180
    Was the Space Shuttle a Mistake?

    Continued at Source
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  3. R29k

    R29k MDL GLaDOS

    Feb 13, 2011
    5,171
    4,811
    180
    Eye of Gaia: billion-pixel camera to map Milky Way

    Source
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  4. UVAIS

    UVAIS MDL Expert

    Mar 17, 2011
    1,333
    1,895
    60
    Sex -- As We Know It -- Works Thanks to Ever-Evolving Host-Parasite Relationships, Biologists Find

    link
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  5. UVAIS

    UVAIS MDL Expert

    Mar 17, 2011
    1,333
    1,895
    60
    Power from the Air: Device Captures Ambient Electromagnetic Energy to Drive Small Electronic Devices

    link
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  6. UVAIS

    UVAIS MDL Expert

    Mar 17, 2011
    1,333
    1,895
    60
    World War II Bombing Raids Offer New Insight Into the Effects of Aviation On Climate


    continue @ link
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  7. UVAIS

    UVAIS MDL Expert

    Mar 17, 2011
    1,333
    1,895
    60
    Climate Pollution From Aviation Increasing

    Complete @ Source:eek:
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  8. UVAIS

    UVAIS MDL Expert

    Mar 17, 2011
    1,333
    1,895
    60
    Atlantis docks with space station

    more
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  9. UVAIS

    UVAIS MDL Expert

    Mar 17, 2011
    1,333
    1,895
    60
    Somalia 'worst humanitarian disaster' in world
    Read full @ Source
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  10. UVAIS

    UVAIS MDL Expert

    Mar 17, 2011
    1,333
    1,895
    60
    Shuttle crew checks for damage on final mission's 1st day

    More..:)
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  11. R29k

    R29k MDL GLaDOS

    Feb 13, 2011
    5,171
    4,811
    180
    The 'Rare Earth' delusion

    In my experience, the most common solution given to the Fermi Paradox is the Rare Earth hypothesis -- the idea that life in the Galaxy is exceptionally rare and that planets like ours are freakishly uncommon. For many, this conveniently explains why we haven't been visited by little green men. Or more accurately, extraterrestrial machine intelligences.

    I've always thought, however, that given cosmologically large numbers that this sort of thinking is symptomatic of our small minds and limited imaginations. It's easy for us to throw up our hands and sheepishly declare that we're somehow special. Such a conclusion, however, needs to be qualified against the data involved, and by the mounting evidence in support of the notion that ours appears to be a life-friendly universe.

    What Do You Mean, 'Rare'?

    Let's pause for a moment and look at the numbers.

    Recent figures place the total number of stars in the Milky way at an astounding three trillion. I don't need to tell you that that is a huge number. But given how poor the human mind is at groking large figures I'm going to play with this number for a bit:
    • 3 trillion fully expressed is 3,000,000,000,000 (12 zeros)
    • As an exponent it can be expressed as 3 x 1012
    • Re-phrased, it is 3 thousand billions, or 3 million millions
    Which necessarily leads to this question: given such a ginormous figure, what does it mean to be rare?

    [​IMG]Even if the Earth is a one in a million occurrence, that means there are still 3 million Earthlike planets in the Galaxy (assuming one Earthlike planet per star). Does that qualify as rare? Not in my books.

    If, on the other hand, the Earth is a one in a billion occurrence, then there are only 3,000 Earths in the galaxy. That sounds a bit more rare to me -- but one in a billion!? Seriously?

    We also have to remember that the 3 trillion stars only accounts for what exists right now in the Milky Way. There have been well over a billion trillion stars in our past Universe. As Charles Lineweaver has noted, planets began forming in our Galaxy as long as 9 billion years ago. We are relative newcomers to the Galaxy.

    Our Biophilic Universe

    But all this numerological speculation might be moot. We're overlooking the mounting evidence indicating that we live in a universe exceedingly friendly to life. What we see in the physical laws and condition of the universe runs contrary to the expectations of the Rare Earthers.

    [​IMG]Indeed, we are discovering that the Galaxy is littered with planets. Scientists have already cataloged 321 extrasolar planets -- a number that increases by a factor of 60 with each passing year. Yes, many of these are are so-called "hot Jupiters," but the possibility that their satellites could be habitable cannot be ruled out. Many of these systems have stable circumstellar habitable zones.
    And shockingly, the first Earthlike planet was discovered in 2007 orbiting the red star Gilese 581. It's only 20 light-years away, 1.5 times the diameter of Earth, is suspected to have water and an atmosphere, and its temperature fluctuates between 0 and 40 degrees Celsius.

    If we are one in a billion, then, and considering that there are only 0.004 stars per cubic light-year, what are the odds that another Earthlike planet is a mere 20 light-years away?

    Indeed, given all this evidence, the Rare Earthers are starting to come under attack. Leading the charge these days is Alan Boss who recently published, The Crowded Universe. Boss estimates that there may be billions of Earthlike planets in the Milky Way alone. "I make the argument throughout the book that we already know that Earths are likely to be incredibly common—every solar-type star probably has a few Earth-like planets, or something very close to it," says Boss. "To my mind, at least, if one has so many habitable worlds sitting around for five billion or 10 billion years, it's almost inevitable that something's going to start growing on the majority of them."

    Life Abounds

    And it gets worse for the Rare Earthers. They also have to contend with the conclusions of astrobiologists.

    It's a myth, for example, that it took life a long time to get going on Earth. In reality it was quite the oppoite. Our planet formed over 4.6 billion years ago and rocks began to appear many millions of years later. Life emerged relatively quickly thereafter some 600 million years after the formation of rocks. It's almost as if life couldn't wait to get going once the conditions were right.

    [​IMG]We also live in a highly fertile Galaxy that's friendly to extremophiles. The Panspermia hypothesissuggests that 'life seeds' have been strewn throughout the Galaxy; evidence exists that some grains of material on Earth have come from beyond our solar system.

    Recent experiments have shown that microorganisms can survive dormancy for long periods of time and under space conditions. We also now know that rocks can travel from Mars to Earth and that simple life is much more resilient to environmental stress than previously imagined. Consequently, biological diversity is probably much larger than conventionally assumed.

    Common Earth

    My feeling is that the Rare Earth hypothesis is a passing scientific fad. There's simply too much evidence growing against it.

    In fact, the only thing going for it is the Fermi Paradox. It's comforting to think that the Great Silence can be answered by the claim that we're exceptionally special. Rare Earth steers us away from other, more disturbing solutions --namely the Great Filter hypothesis.

    But such is the nature of scientific inquiry. We're not always going to like what we find, even if it is the truth.

    As for the Fermi Paradox, we'll have to look for answers elsewhere.

    Source
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  12. R29k

    R29k MDL GLaDOS

    Feb 13, 2011
    5,171
    4,811
    180
    Bulldozer performance figures are in

    Outpaces Sandy Bridge in early tests
    The donanimhaber.com crew has run an engineering sample of AMD’s new FX-8130P through its paces and the results are very positive.

    Although the chip fails to keep up with Intel cores in the SuperPI test, as we have already seen, it pulls ahead in other tests. For example, in x264 encoding tests, Bulldozer scores 136fps in the first pass and 45fps in the second pass, whereas the Core i7 2600K manages 100fps and 36fps respectively.

    Bulldozer manages to stay ahead in 3Dmark 11 tests as well. It scores P6250, while the 2600K hovers around the 6000 mark. In Cinebench R10 AMD’s new flagship pulls off a score of 24434 and outpaces the 2600K, but it ends up somewhat slower than the Core i7 990X.

    Compared to the Thuban-based Phenom II X6 1100T, Bulldozer ends up about 50 percent faster in most tests, which is equally impressive.

    It’s still too early to render a verdict, but at this point Bulldozer looks like a winner, especially if AMD manages to keep the price around the rumoured $320 mark. With Brazos and Llano doing fine, Bulldozer could be the last piece of the puzzle that turns things around for AMD in the high end. For the first time in years, AMD will truly have a competitive line up across its product range.

    More here.
    E
    nglish Translation
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  13. R29k

    R29k MDL GLaDOS

    Feb 13, 2011
    5,171
    4,811
    180
    Hubble Finds Thousands of Gaseous Fragments Surrounding a Dying Star

    [​IMG]

    ABOUT THIS IMAGE: These gigantic, tadpole-shaped objects are probably the result of a dying star's last gasps. Dubbed "cometary knots" because their glowing heads and gossamer tails resemble comets, the gaseous objects probably were formed during a star's final stages of life.
    Hubble astronomer C. Robert O'Dell and graduate student Kerry P. Handron of Rice University in Houston, Texas discovered thousands of these knots with the Hubble Space Telescope while exploring the Helix nebula, the closest planetary nebula to Earth at 450 light-years away in the constellation Aquarius. Although ground-based telescopes have revealed such objects, astronomers have never seen so many of them. The most visible knots all lie along the inner edge of the doomed star's ring, trillions of miles away from the star's nucleus. Although these gaseous knots appear small, they're actually huge. Each gaseous head is at least twice the size of our solar system; each tail stretches for 100 billion miles, about 1,000 times the distance between the Earth and the Sun. Astronomers theorize that the doomed star spews hot, lower-density gas from its surface, which collides with cooler, higher-density gas that had been ejected 10,000 years before. The crash fragments the smooth cloud surrounding the star into smaller, denser finger-like droplets, like dripping paint.
    This image was taken in August, 1994 with Hubble's Wide Field Planetary Camera 2. The red light depicts nitrogen emission ([NII] 6584A); green, hydrogen (H-alpha, 6563A); and blue, oxygen (5007A).
    Object Name: Helix Nebula
    Image Type: Astronomical
    Credit: C. Robert O'Dell and Kerry P. Handron (Rice University), NASA

    Source
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  14. R29k

    R29k MDL GLaDOS

    Feb 13, 2011
    5,171
    4,811
    180
    Humans and Aliens Might Share DNA Roots

    The building blocks of life may be more than merely common in the cosmos. Humans and aliens could share a common genetic foundation.
    That’s the tantalizing implication of a pattern found in the formation of amino acids in meteorites, deep-sea hydrothermal vents, and simulations of primordial Earth. The pattern appears to follow basic thermodynamic laws, applicable throughout the known universe.
    "This may implicate a universal structure of the first genetic codes anywhere," said astrophysicist Ralph Pudritz of McMaster University in Hamilton, Ontario.
    There are exactly 20 standard amino acids — complex molecules that combine to form proteins, which carry out instructions specified by RNA and DNA, its double-stranded and self-replicating descendant.
    Ten were synthesized in the famous 1953 Miller-Urey experiments, which modeled conditions believed to exist in Earth’s early atmosphere and volcano-heated pools. Those 10 amino acids have also been found in meteorites, prompting debate over their role in sparking life on Earth and, perhaps, elsewhere.
    Pudritz’s analysis, co-authored with McMaster University biophysicist Paul Higgs and published Monday on arXiv, doesn’t settle the former debate, but it does suggest that basic amino acids are even more common than thought, requiring little more than a relatively warm meteorite of sufficient size to form. And that’s just the start.
    If the observed patterns of amino acid formation — simple acids require low levels of energy to coalesce, and complex acids need more energy — indeed follow thermodynamic laws, then the basic narrative of life’s emergence could be universal.
    "Thermodynamics is fundamental," said Pudritz. "It must hold through all points of the universe. If you can show there are certain frequencies that fall in a natural way like this, there is an implied universality. It has to be tested, but it seems to make a lot of sense."
    [​IMG]Pudritz and Higgs tabulated the types and frequencies of amino acids found in primordial Earth experiments, then correlated the results on a graph of temperature versus atmospheric pressure at which the acids likely formed.
    The 10 amino acids synthesized in primordial Earth experiments tended to arise at relatively low temperatures and pressures, and are chemically simple. Other, more complex acids formed less frequently, and require more temperature and pressure. Their distribution follows a clear, possibly thermodynamic, curve.
    "The most frequent amino acid that forms is the one that’s least-demanding, energetically. There’s less and less amino acids that require more energy to form. That’s very sensible, from a thermodynamic point of view," said Pudritz.
    Internal conditions of meteorites are unknown, but some scientists believe that certain large meteorites are both warm and hydrated, making them roughly analogous to the relatively temperate environment of Earth’s youth.
    "There’s a theory," said Pudritz, "that they could be made in the warm interiors of large-enough meteorites."
    This is necessarily speculative, but it would explain why the 10
    amino acids most common in primordial Earth experiments are also the most common acids found in meteorites.
    Pudritz and Higgs speculate that these 10 common amino acids met the needs of the earliest replicating molecules, with other, rarer acids used by the nascent genetic code as they formed or arrived — a process called "stepwise evolution," culminating in the genes that gathered 3.6 billion years ago in a common ancestor of all complex life.
    If simulations of interactions between these 10 acids indeed support molecules that can copy themselves, said Pudritz, then it’s possible that they could support an ur-genetic code on Earth and elsewhere.
    "There’s a possible universality," he said, "for any code that would use amino acids."
    Harvard University systems biologist Irene Chen, who specializes in the evolution of molecules, called the work
    "interesting," but noted that "in the absence of some experimental backup, it’s generally difficult to know if this kind of analysis is a
    Panglossian argument."
    The ultimate experimental backup, of course, is finding aliens. In the meantime, the ending of Battlestar Galactica seems a bit less implausible.
    Citation: "A thermodynamic basis for prebiotic amino acid synthesis and the nature of the first genetic code." By Paul G. Higgs, Ralph E.
    Pudritz. arXiv, April 6, 2009.

    Source
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  15. 60cent

    60cent MDL Senior Member

    May 31, 2011
    437
    514
    10
    Interesting Facts About Planet Mars

    by Fraser Cain on June 5, 2008


    Here are a few interesting facts about Mars that you can use to amaze your friends.


    1. Mars is actually pretty small.

    You might think that Mars is a near-twin of Earth, but it has a diameter of about half the Earth, measuring only 6,800 km across. With the smaller size comes an even smaller mass. The total mass of Mars is only about 10% the mass of Earth. The surface gravity is only 37% what you would experience on Earth. In other words, you would be able to jump 3 times as high on Mars as you can on Earth.

    2. People used to think it had water and canals

    Before the first spacecraft arrived at Mars in 1965, nobody had ever seen Mars up close. Dark blotches on the surface of the Red Planet were interpreted as lakes or oceans, and some people even thought they could seen dark lines crisscrossing the surface of the planet. They imagined these might be the irrigation canals of a dying civilization. It turned out these were just an optical illusion, and Mars is a dry dusty desert.

    3. But Mars really does have water

    Mars might not have oceans, rivers and lakes, but NASA’s Mars Odyssey spacecraft detected huge deposits of water underneath the surface, across the planet – in the form of ice. The Phoenix mission has arrived on Mars to search for ice underneath the soil at the northern polar cap. It has all the tools on board to analyze the water ice to see if has any traces current or ancient life.

    4. Mars has the tallest mountain in the Solar System

    The tallest mountain in the Solar System is the mighty Olympus Mons on Mars. It rises up 27 kilometers above the surrounding plains. Olympus Mons is a shield volcano, like Hawaii’s Mauna Kea, and formed gradually over billions of years. Some lava flows on the volcano are so young that planetary scientists think that it might still be active.

    5. And Mars has the longest, deepest canyon in the Solar System

    One of the most distinct features on the surface of Mars is the Valles Marineris canyon. It stretches 4,000 km along the equator of Mars, and can be as deep as 7 km in places. If you could move the Valles Marineris to Earth, it would stretch right across the United States.

    6. We have pieces of Mars on Earth

    Both Earth and Mars have been slammed by large asteroids in the past. Although most of the debris kicked up by the impact falls back down on to the planet, some of it can be ejected so quickly that it escapes Mars entirely. These ejected meteorites can orbit the Solar System for millions of years before they finally crash down on other worlds. Some have crashed on Earth, and been identified by scientists. Tiny amounts of Mars’ atmosphere were trapped in the meteorites, and this is how scientists were able to study the Martian atmosphere before sending the first spacecraft.

    7. One of Mars’ moons is going to crash into it

    Mars has two, tiny asteroid-sized moons called Phobos and Deimos. Phobos orbits the planet at such a low altitude that it’s going to eventually be torn apart by the gravity of Mars. It will survive as a ring for a few years, and then the debris will rain down on Mars. Scientists disagree on when this will happen. It could happen as soon as 10 million years from now, and no later than 50 million years.

    8. Mars has almost no atmosphere

    If you tried to stand out on the surface of Mars without a spacesuit, you would die almost immediately. The freezing cold temperatures would be a problem, but even worse is the thin atmosphere. The air pressure at the surface of Mars is only 1% the pressure we enjoy here on Earth. And the atmosphere on Mars consists of 95% carbon dioxide, 3% nitrogen, 1.6% argon and trace amounts of water and oxygen.

    9. Mars is crawling and buzzing with spacecraft

    At the time of this writing, there are three spacecraft down on the surface of Mars, NASA’s Spirit and Opportunity rovers, as well as the Phoenix Mars lander. And there are three orbiters watching from orbit: NASA’s Mars Reconnaissance Orbiter, Mars Odyssey and ESA’s Mars Express. No other planet in the Solar System has ever been so well studied.

    10. And more spacecraft are on their way to Mars

    Every two years, Mars and Earth line up so that missions can be sent with a minimum amount of fuel. NASA has plans to send one of their most ambitious missions to date: the Mars Science Laboratory. This will be an SUV-sized laboratory that can crawl across the surface of Mars for months and months, searching for past and current evidence of life.

    In the future there could be airplanes and balloons, subsurface explorers, and maybe even sample return missions, to bring a little piece of Mars back to Earth. And one day, humans will finally step foot on the Red Planet. Maybe even within our lifetime.

    I hope you enjoyed these interesting facts about planet Mars.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  16. Spider-Vice

    Spider-Vice MDL Member

    Mar 30, 2011
    248
    302
    10
    #56 Spider-Vice, Jul 13, 2011
    Last edited: Jul 13, 2011
    Mount Etna eruption closes airports and 'knocks clocks 15 minutes fast'


     
  17. R29k

    R29k MDL GLaDOS

    Feb 13, 2011
    5,171
    4,811
    180
    Are you living in a computer simulation?

    continued at source

     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  18. UVAIS

    UVAIS MDL Expert

    Mar 17, 2011
    1,333
    1,895
    60
    :eek::eek::eek:

    Thanks :cool:
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  19. half Man Half Biscuit

    half Man Half Biscuit MDL Addicted

    Jun 1, 2011
    684
    922
    30
    The Greatest Ocean Depth:


    Challenger Deep in the Mariana Trench is the deepest point in Earth's oceans. The bottom there is 10,924 meters (35,840 feet) below sea level. If Mount Everest, the highest mountain on Earth, were placed at this location it would be covered by over one mile of water. The Challenger Deep is named after the British survey ship Challenger II, which discovered this deepest location in 1951.


    Map of the Mariana Trench - Deepest Point in Earth's Oceans - Image by CIA
    [​IMG]
    Exploring the Challenger Deep


    The Challenger Deep was first explored by Jacques Piccard and Don Walsh in the Trieste bathyscaphe in 1960. They reached a depth of 10,916 meters (35,814 feet). In 2009 researchers from Woods Hole Oceanographic Institution completed the deepest dive by an unmanned robotic vehicle in the Challenger Deep. Their Nereus robotic vehicle reached a depth of 10,902 meters.


    Why is the ocean so deep here?


    The Mariana Trench is located at a convergent plate boundary. Here two converging lithospheric plates collide with one another. At this collision point, one of the plates descends into the mantle. At the line of contact between the two plates the downward flexure forms a trough known as an ocean trench. An example of an ocean trench is shown in the diagram below.
    [​IMG]

    USGS Image.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  20. half Man Half Biscuit

    half Man Half Biscuit MDL Addicted

    Jun 1, 2011
    684
    922
    30
    Giant Lost Island Found on Atlantic Seafloor



    [​IMG]

    A 10,000 square kilometer (3,861 sq. mile) island sank beneath the waves long ago, in the frigid waters of the Atlantic north of Scotland.

    No, it wasn't Atlantis.

    The landmass sank beneath the waves of the North Atlantic long before humans arrived on the scene.

    The island was created when the Icelandic Plume, a bubble of magma beneath the Earth’s surface, forced the crust up and out of the water. The land was forced up in a series of three steps, each one pushing the land 200-400 meters higher.

    The island popped up out of the water for about a million years. Long enough for land plants to colonize it. But it sank back down and now resides almost 2 kilometers (1.2 miles) beneath the ocean.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...