The twin probesSTEREO, NASA, are currently traversing a mysterious region of space in search of remains of aancient planetwhich may have revolved around the Sun, not far from Earth. His name isTheiaand, although no one has ever seen it, “some researchers believe it existed long ago.4.5 billion yearsand that it collided with the Earth thus causing the formation of theMonth“explains Mike Kaiser, STEREO project scientist.
The call“Theia hypothesis”was formulated by Edward Belbruno and Richard Gott and postulates that, during the formation of the solar system, after the collision between a protoplanet the size of Mars and the Earth, a mixture of material from both planets was expelled into space that kept rotating in the around the Earth, and later merged creating the Moon. This scenario would explain many aspects of lunar geology, including the size of the Moon’s core.
However, the theory raises a question: where did this huge protoplanet come from? Belbruno and Gott believe it came from one of the so-calledLagrange pointsof the Sun-Earth system, regions of space where the gravitational pull of the Earth and the Sun combine to form a “gravitational well.” When the solar system was still very young, the Lagrange points were mainly populated by planetesimals, or asteroid-sized units that made up the planets. Belbruno and Gott suggest that at one of the Lagrange points, possibly L4 or L5, the planetesimals came together to form Theia, whose name in Greek mythology represented a titan who gave birth to the moon goddess, Selena.
If the STEREO probes find in L4 and L5 remains of the Theia formation, the size of asteroids, with the same composition as the Earth and the Moon, it would confirm the version of Belbruno and Gott on the theory of theHigh impact.
