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Thread: Current Events in Astronomy

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    Lead Moderator calikid's Avatar
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    Current Events in Astronomy

    Interesting current events about the study of the heavens.
    The aim of an argument or discussion should not be victory, but
    progress. -- Joseph Joubert
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    Will researchers finally be able to directly photograph a black hole?

    What Will First Photos of Black Holes Look Like?

    By Clara Moskowitz | SPACE.com

    A giant black hole is thought to lurk at the center of the Milky Way, but it has never been directly seen. Now astronomers have predicted what the first pictures of this black hole will look like when taken with technology soon to be available.

    In particular, researchers have found that pictures of a black hole ? or, more precisely, the boundaries around them ? will take a crescent form, rather than the blobby shape that is often predicted.

    By modeling what these pictures will look like, scientists say they are preparing to interpret the photos that will become available from telescopes currently under construction.

    "No one has been able to image a black hole," said University of California, Berkeley student Ayman Bin Kamruddin, who presented a poster on the research last week in Long Beach, Calif., at the 221st meeting of the American Astronomical Society. "So far it's been impossible because they're too small in the sky. Right now we're just getting some details about the structure, but we don't have an image yet." [Gallery: Black Holes of the Universe]

    Black holes themselves are invisible, of course, as not even light can escape their gravitational clutches. However, the boundary of a black hole — the point of no return called the event horizon — should be visible from the radiation emitted by matter falling into the black hole.

    "A black hole's immediate surroundings have a lot of really interesting physics going on, and they emit light," Kamruddin said. "Technically speaking, we aren't exactly seeing the black hole, but we are effectively resolving the event horizon."

    A new project called the Event Horizon Telescope combines the resolving power of numerous antennas from a worldwide network of radio telescopes to sight objects that otherwise would be too tiny to make out.

    "The Event Horizon Telescope is the first to resolve spatial scales comparable to the size of the event horizon of a black hole," said Kamruddin's collaborator, University of California, Berkeley astronomer Jason Dexter. "I don't think it's crazy to think we might get an image in the next five years."

    The Event Horizon Telescope already has been gathering some preliminary measurements of the object called Sagittarius A* (pronounced "Sagittarius A-star") at the center of our Milky Way galaxy.

    Kamruddin and Dexter have matched this data to various physical models and found that they best fit images that are crescent-shaped, rather than the blob shapes called "asymmetric Gaussians" that had been previously used in models.

    The crescent shape emerges from the flat doughnut, called an accretion disk, formed by matter orbiting a black hole on its way to falling in. As gas spins around the black hole, one side of the disk comes toward view on Earth, and its light becomes brighter because of a process called Doppler beaming. The other side, representing receding gas, gets dimmer because of this effect.

    In the center of the crescent is a dark circle called the black hole shadow, which represents the black hole itself — an incredibly dense object where space-time is extremely twisted.

    "There's really extreme bending of light happening because of general relativity and the extremely strong gravitational field," Kamruddin said. Story Continues
    The aim of an argument or discussion should not be victory, but
    progress. -- Joseph Joubert
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    Lead Moderator calikid's Avatar
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    The journey to another star sytem begins with leaving our solar system.
    Voyager 1 becomes first human-made object to leave solar system

    By Elizabeth Landau

    At the edge of the heliosphere, you wouldn't know by looking whether you left the cradle of humanity behind and floated out into interstellar space. You would just see unfathomably empty space, no matter which side of the invisible line you were on.

    But scientists now have strong evidence that NASA's Voyager 1 probe has crossed this important border, making history as the first human-made object to leave the heliosphere, the magnetic boundary separating the solar system's sun, planets and solar wind from the rest of the galaxy.

    "In leaving the heliosphere and setting sail on the cosmic seas between the stars, Voyager has joined other historic journeys of exploration: The first circumnavigation of the Earth, the first steps on the Moon," said Ed Stone, chief scientist on the Voyager mission. "That's the kind of event this is, as we leave behind our solar bubble."

    A new study in the journal Science suggests that the probe entered the interstellar medium around August 25, 2012. You may have heard other reports that Voyager 1 has made the historic crossing before, but Thursday was the first time NASA announced it. Story Continues
    The aim of an argument or discussion should not be victory, but
    progress. -- Joseph Joubert
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  4. #4
    Quote Originally Posted by calikid View Post
    The journey to another star sytem begins with leaving our solar system.
    Voyager 1 becomes first human-made object to leave solar system

    By Elizabeth Landau

    At the edge of the heliosphere, you wouldn't know by looking whether you left the cradle of humanity behind and floated out into interstellar space. You would just see unfathomably empty space, no matter which side of the invisible line you were on.

    But scientists now have strong evidence that NASA's Voyager 1 probe has crossed this important border, making history as the first human-made object to leave the heliosphere, the magnetic boundary separating the solar system's sun, planets and solar wind from the rest of the galaxy.

    "In leaving the heliosphere and setting sail on the cosmic seas between the stars, Voyager has joined other historic journeys of exploration: The first circumnavigation of the Earth, the first steps on the Moon," said Ed Stone, chief scientist on the Voyager mission. "That's the kind of event this is, as we leave behind our solar bubble."

    A new study in the journal Science suggests that the probe entered the interstellar medium around August 25, 2012. You may have heard other reports that Voyager 1 has made the historic crossing before, but Thursday was the first time NASA announced it. Story Continues
    Good story. We don't hear enough from mainstream media on outer space.

  5. #5
    Lead Moderator calikid's Avatar
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    Plasma, the fourth state of matter, something I always associated with burning gas, not water!
    Strange Super-Earth Planet Has 'Plasma' Water Atmosphere
    by Nola Taylor Redd

    A nearby alien planet six times the size of the Earth is covered with a water-rich atmosphere that includes a strange "plasma form" of water, scientists say.

    Astronomers have determined that the atmosphere of super-Earth Gliese 1214 b is likely water-rich. However, this exoplanet is no Earth twin. The high temperature and density of the planet give it an atmosphere that differs dramatically from Earth.

    "As the temperature and pressure are so high, water is not in a usual form (vapor, liquid, or solid), but in an ionic or plasma form at the bottom the atmosphere — namely the interior — of Gliese 1214 b," principle investigator Norio Narita of the National Astronomical Observatory of Japan told SPACE.com by email.

    Using two instruments on the Subaru Telescope in Mauna Kea, Hawaii, scientists studied the scattering of light from the planet. Combining their results with previous observations led the astronomers to conclude that the atmosphere contained significant amounts of water.
    Story Continues
    The aim of an argument or discussion should not be victory, but
    progress. -- Joseph Joubert
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    This galaxy appears as less than 1B years old. Just a baby!

    Scientists confirm most distant galaxy ever

    By Elizabeth Landau

    Scientists say they've found a galaxy that's not just far, far, away -- it's the most distant from our own that's been discovered yet. And it's helping them gain insight about the universe as it existed a long time ago.

    Astronomers say the galaxy, called z8_GND_5296, is the most remote one they can confirm with spectroscopy, a technique that looks for the chemical signatures of elements.

    In this case, that element was hydrogen, the main fuel of stars. Researchers reported their findings in the journal Nature.

    z8_GND_5296 -- no, that's not a typo, or a spam username -- is a window into the past. Because of its distance, it shows what things would have been like 700 million years after the Big Bang.

    The universe is 13.8 billion years old, so 700 million years after the start is actually quite early by comparison.

    Star formation

    Besides breaking the distance record, astronomers find the new galaxy exciting because it appears to produce stars at an unusually high rate, said lead study author Steven Finkelstein, assistant professor of astronomy at the University of Texas at Austin.

    Star-formation rate is measured by how much raw hydrogen the galaxy converts into new stars every year. The z8_GND_5296 galaxy converts hydrogen in the amount of 300 times the mass of our sun into new stars each year.

    By contrast, the Milky Way only produces stars at one or two solar masses per year.

    Scientists established through previous research that in the first billion years of the universe's history, typical rate of star formation went up, Finkelstein said. Galaxies formed more and more stars over time until about 10 billion years ago, when star formation rates began to decrease.
    Story Continues
    The aim of an argument or discussion should not be victory, but
    progress. -- Joseph Joubert
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    Lead Moderator calikid's Avatar
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    Many places ET might call home.

    Earthshaking news: There may be other planets like ours
    Doyle Rice
    There are likely 40 billion Earth-like planets in our Milky Way galaxy, astronomers say.

    We are not alone.

    There are likely "tens of billions" of Earth-like planets in our Milky Way galaxy, according to a study released Monday by astronomers from the University of California-Berkeley and the University of Hawaii.

    "Planets like our Earth are relatively common throughout the Milky Way galaxy," said astronomer Andrew Howard of the University of Hawaii, who estimates the number at about 40 billion.

    In fact, the nearest Earth-like planet may be "only" 12 light years away, which is roughly 72 trillion miles.

    In all, about 8.8 billion stars in our galaxy have planets that are nearly the size of Earth and also have a surface temperature conducive to the development of life. But many more stars (those not similar to our sun) also have planets where life could form, which is where the 40 billion-planet figure comes from.

    Like Goldilocks tasting the porridge, temperatures must be "just right" for life to develop: Planets must have a so-called "habitable zone" with "lukewarm temperatures, so that water would not be frozen into ice or vaporized into steam but instead remain a liquid, because liquid water is now understood to be the prerequisite for life," said Geoffrey Marcy, a professor of astronomy at Berkeley.

    The discovery was based on the most accurate statistical analysis yet of all the observations from the Kepler telescope, a space observatory launched in 2009 specifically designed to locate planets around other stars. Story Continues
    The aim of an argument or discussion should not be victory, but
    progress. -- Joseph Joubert
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    Always nice to establish proof for a theory, and rule out competing theories.


    Gravitational Waves from Big Bang Detected
    A curved signature in the cosmic microwave background light provides proof of inflation and spacetime ripples
    By Clara Moskowitz

    Physicists have found a long-predicted twist in light from the big bang that represents the first image of ripples in the universe called gravitational waves, researchers announced today. The finding is direct proof of the theory of inflation, the idea that the universe expanded extremely quickly in the first fraction of a nanosecond after it was born. What’s more, the signal is coming through much more strongly than expected, ruling out a large class of inflation models and potentially pointing the way toward new theories of physics, experts say.

    “This is huge,” says Marc Kamionkowski, professor of physics and astronomy at Johns Hopkins University, who was not involved in the discovery but who predicted back in 1997 how these gravitational wave imprints could be found. “It’s not every day that you wake up and find out something completely new about the early universe. To me this is as Nobel Prize–worthy as it gets.”

    The Background Imaging of Cosmic Extragalactic Polarization 2 (BICEP2) experiment at the South Pole found a pattern called primordial B-mode polarization in the light left over from just after the big bang, known as the cosmic microwave background (CMB). This pattern, basically a curling in the polarization, or orientation, of the light, can be created only by gravitational waves produced by inflation. “It looks like a swirly pattern on the sky,” says Chao-Lin Kuo, a physicist at Stanford University, who designed the BICEP2 detector. “We’ve found the smoking gun evidence for inflation and we’ve also produced the first image of gravitational waves across the sky.”

    Such a groundbreaking finding requires confirmation from other experiments to be truly believed, physicists say. Nevertheless, the result has won praise from many leaders in the field.Story continues
    The aim of an argument or discussion should not be victory, but
    progress. -- Joseph Joubert
    Attachment 1008

  9. #9
    Total Lunar Eclipse For Much Of U.S. April 14th ,15th Depending on your location.

    Check table in link for your location-

    http://www.vercalendario.info/en/moo...pril-2014.html

    Enjoy !

    Cliff-67
    Attached Images Attached Images
    Last edited by touched; 03-21-2014 at 10:47 PM.
    Amateur Astronomer/38 years - Cliff-67

  10. #10
    Lead Moderator calikid's Avatar
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    Quote Originally Posted by touched View Post
    Total Lunar Eclipse For Much Of U.S. April 14th ,15th Depending on your location.

    Check table in link for your location-

    http://www.vercalendario.info/en/moo...pril-2014.html

    Enjoy !

    Cliff-67
    Cool, Max eclipse a little past midnight on April 14, 2014 here in California. I'm even working outside that night, hope the cloud cover cooperates!
    The aim of an argument or discussion should not be victory, but
    progress. -- Joseph Joubert
    Attachment 1008

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