Photobucket - Video and Image Hosting Photobucket - Video and Image Hosting Photobucket - Video and Image Hosting "Bold is the ship bound for Alpha Centauri, nothing can turn it around..." Since Star Trek has not yet become a reality, we must ride the bold spaceship of our imagination and view the wonders of the universe through pictures taken by telescopes. Thanks to Hubble and others, we can emulate Captain Picard and say, "Let's see what's out there." Glories and Wonders! How great Thou art!
  • Mad is the Captain of Alpha Centauri; We must be out of our minds. Still we are shipmates bound for tomorrow, and everyone here's flying blind. Mad is the crew bound for Alpha Centauri, Dreamers and poets and clowns. Bold is the crew bound for Alpha Centauri; nothing can turn it around. Oh, we must believe in magic; we must believe in the guiding hand. If you believe in magic, you'll have the universe at your command. Artist:Crystal Gayle; album UNKNOWN
  • Tuesday, August 11, 2009


    Lost Planet - Birth of Moon

    search for earth's lost planet (moon's source)

    Also see:
    [earlier theory]

    The Search for the Solar System's Lost Planet
    By Clara Moskowitz
    Staff Writer
    posted: 13 April 2009
    09:42 am ET

    The solar system might once have had another planet named Theia, which may have helped create our own planet's moon.

    Now two spacecraft are heading out to search for leftovers from this rumored sibling, which would have been destroyed when the solar system was still young.

    "It's a hypothetical world. We've never actually seen it, but some researchers believe it existed 4.5 billion years ago — and that it collided with Earth to form the moon," said Mike Kaiser, a NASA scientist at the Goddard Space Flight Center in Maryland.

    Theia is thought to have been about Mars-sized. If the planet crashed into Earth long ago, debris from the collision could have clumped together to form the moon. This scenario was first conceived by Princeton scientists Edward Belbruno and Richard Gott.

    Many researchers now figure that indeed some large object crashed into Earth, and the resulting debris coalesced to form the moon. It is unclear though if that colliding object was a planet, asteroid or comet.

    In any case, the debris that would have spun out from the two slamming bodies would have mixed together, and could explain some aspects of the moon's geology, such as the size of the moon's core and the density and composition of moon rocks.

    Scientists are hoping NASA's twin STEREO probes, launched in 2006, will be able to discover leftover traces of Theia that may finally help close the case on the birth of our moon.

    So far, signs of Theia have proved elusive to telescopes searching from Earth. But the STEREO spacecraft are set to enter special points in space, called Lagrangian points, where the gravity from the Earth and the sun combine to form wells that tend to collect solar system detritus. [Click here for an animation that explains Lagrangian points.]

    where did Theia come from?


    Lagrangian points exist in any two-body system. This multimedia presentation shows how it works with the Earth-Moon system. The same setup applies with the Sun-Earth as it relates to the Gott and Belbruno work. View It.

    "The STEREO probes are entering these regions of space now," Kaiser, a STEREO project scientist, said. "This puts us in a good position to search for Theia's asteroid-sized leftovers."

    By visiting the Lagrangian points directly, STEREO will be able to hunt for Theia chunks up close. The nearest approach to the bottoms of the gravitational wells will come in September and October 2009.

    "STEREO is a solar observatory," Kaiser said. "The two probes are flanking the sun on opposite sides to gain a 3-D view of solar activity. We just happen to be passing through the L4 and L5 Lagrange points en route. This is purely bonus science."

    Scientists think Theia may even have formed in one of these gravitational points of balance from the accumulation of flotsam that had built up there.

    "Computer models show that Theia could have grown large enough to produce the moon if it formed in the L4 or L5 [Lagrangian] regions, where the balance of forces allowed enough material to accumulate," Kaiser said. "Later, Theia would have been nudged out of L4 or L5 by the increasing gravity of other developing planets like Venus and sent on a collision course with Earth."


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