Astronomers are hoping to catch a glimpse of debris that could be leftover from a cosmic collision between our Earth and a Mars-sized planet called Theia–if, in fact, it existed at all. “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 [SPACE.com].
The research will be done with the two Stereo spacecraft that are on their way to observe the sun; on their way they’ll have a chance to do some “bonus science,” as one researcher called it. The spacecraft are passing through two regions of space, called Lagrangian points, where the gravity from the Earth and the sun combine to form wells that tend to collect solar system detritus…. 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 [SPACE.com].
According to one theory of our moon‘s origin, the gravitational pull of Venus may have tugged Theia out of its stable spot, and sent it careening into Earth. The glancing blow stripped the impactor of its outer layer, along with some of Earth’s. Its iron core is thought to have melted and much of it merged with Earth’s iron core. The outer material – mostly belonging to the impactor – gathered itself together and formed the moon. [This theory] explains why the moon has such a tiny iron core. It also explains why the the geochemistry of Earth and moon materials are so similar – they formed in the same region of the nebula of dust and gas that surrounded the early sun [The Christian Science Monitor].
Astronomers have looked for large “Theiasteroids” in the Lagranian points with ground-based telescopes, with little success. But the Stereo spacecraft will have a better view that will allow it to search for smaller asteroid chunks. The spacecraft pair will also study the mineral composition of any asteroids it sights to determine if they’re chemically similar to Earth or the moon.
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DISCOVER: Geophysics: Is the Earth’s inner core simply the other half of our only satellite?
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Image: NASA
April 19th, 2009 at 6:33 am
Anyone familiar with Zacharia Sitchin’s work illuminating the ancient writings of the Sumerians will be well and truly aware of the “cosmic struggle” that took place 4.1 billion years ago in our own solar system. In his book THE TWELFTH PLANET Sitchen explains that Niberu came very close to Tiamat, a planet several times larger than earth, and one of its many moon stuck Tiamat, cleaving the planet in two. The Sumerians explained on their clay tablets, that the collision had very much the effects listed above. Tiamat’s rubble formed the asteroid belt and many comets. Its other half, now called Earth, was catapulted into its new (present) position. The moon was captured from Niburu. Many other consequences of the collision, including the origin of the iron core and the collision’s effect on the orbits of other planets are explained. THE TWELFTH PLANET is a provocative and mind expanding read.
July 17th, 2009 at 2:29 pm
The 12th planet is speculative/conjecture at best. Sitchin took so many liberties in his research and made so many assumptions in his translations that his writing can’t be considered science.
I’ve read his books and they’re entertaining but until any of it can be proven independently and irrefutabily, they’re just entertainment.
July 20th, 2009 at 1:06 pm
Actually, he did predict the existence of Pluto before it was discovered. I’ve always had issues with the math aspect regarding Nibiru’s orbit, but it seems like I think of those books about once or twice a year when I see a story that is VERY similar. I think, based on numerous facts, that it would be wise to heed the work by at least trying to design some experiments to verify or refute his findings. It shouldn’t be that hard to attach them to a mission that’s already planned.
July 20th, 2009 at 2:18 pm
“Actually, he did predict the existence of Pluto before it was discovered. ”
Pluto was discovered on February 18th 1930 by Clyde W. Taumbaugh. I think Sitchin was still in grade school then.
July 21st, 2009 at 4:18 am
Nibiru isnt real. The scenario outlined by Sitchin, with Nibiru returning to the inner solar system regularly every 3,600 years, implies an orbit with a semi-major axis of 235 Astronomical Units, extending from the asteroid belt to twelve times farther beyond the sun than Pluto. This would mean that Nibiru spends 99% of its time beyond pluto. Those conditions are way to cold to sustain life. “Elementary perturbation theory indicates that, under the most favorable circumstances of avoiding close encounters with other planets, no body with such an eccentric orbit would keep the same period for two consecutive passages. Within twelve orbits the object would be either ejected or converted to a short period object. Not to mention that Sitchin’s translations of both individual words and of larger portions of ancient texts are generally found to be incorrect by his colleagues. Sitchin bases his arguments on his personal interpretations of Pre-Nubian and Sumerian texts, and the seal VA 243. Sitchin claims these ancient civilizations knew of a 12th planet, when in fact they only knew five. Hundreds of Sumerian astronomical seals and calendars have been decoded and recorded, and the total count of planets on each seal has been five. Seal VA 243 has 12 dots that Sitchin identifies as planets. When translated, seal VA 243 reads “You’re his Servant” which is now thought to be a message from a nobleman to a servant. According to semitologist Michael S. Heiser, the so-called sun on Seal VA 243 is not the Sumerian symbol for the sun but is a star, and the dots are also stars. The symbol on seal VA 243 has no resemblance to the hundreds of documented Sumerian sun symbols.