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Tuesday, June 12, 2012

Enlarge the probability of an asteroid crash with Earth


Scientists at the Cardiff Centre of Astrobiology, UK, have developed a mathematical model that confirms that currently is experience our solar system called the extensive hydroplane, which increase the chances of an asteroid collide with Earth. An asteroid is a rocky body that orbits the Sun Becomes meteorite when it enters Earth's atmosphere. In astronomy, is called the huge hydroplane in the middle of the region in which they are most of the stars of a flattened galaxy, as twist galaxies.
This plane passes through the center of the galaxy. As reported by the magazine TFOT, scientists say that our solar system crosses the galactic plane of the Milky Way every 35-40 million years. In the past, travel the solar system through the galactic plane coincided with mass extinctions of life on Earth, his collision against him by a large meteorite. Extinctions Past The mathematical model created by researchers shows that Sun, "jumps" up and down through the galactic plane of the Milky Way and, as goes through the densest parts of the plane, gravitational forces push the comet out of their paths and rush into the solar system. As a result, the probability that a meteorite reaches the Earth increases. Teachers Janaki Wickramasinghe and Bill Napier, from the center, explained in the Monthly Notices of the Royal Astronomical Society that the model allows calculating the flux of comets that have penetrated in the solar system from the so-called Out cloud during earlier periods. The Out Cloud is a cloud of comets that is believed to be located on the edge of the solar system, at an approximate distance of 100,000 AU (AU is one astronomical unit which equals 149,597,870 kilometers). Statistically, it is estimated that between one and hundred billion comets, with a total mass may exceed that of Jupiter. Although never observed directly, it is believed that the Out cloud would consist of the "wreckage" of our planetary system, which envelop like a balloon. According to Wickramasinghe and Napier, episodes of "bombing" extra comets solar system produce characteristic time scales of 25 to 35 million years, especially in periods when the solar system crosses the galactic plane. Danger Future In fact, the theoretical expectations of the mathematical model coincide in time with the age of the meteorite impact craters on Earth appeared in the last 250 million years. For years the scientific community concluded that at least two mass extinctions of terrestrial life forms have taken place over a period of crossing of the solar system through the galactic plane. The model of Cardiff researchers with new evidence supports this theory. According to astronomers, the solar system's last encounter with one of the luminous arms of the Milky Way (star formation containing arms) occurred 65 million years. This meeting resulted in the extinction of most dinosaurs and almost 60% of plant life on our planet. The mathematical model has been derived both from the records of the impact craters and the sun's position with respect to galactic plane, which is currently going through a similar period. For this reason caution that should be allocated more resources and effort in finding the so-called "near-Earth objects" (in English the "NEO"), which are those comets or asteroids, trapped by the attraction of the sun or of the various planets in orbit around it, could end up getting dangerously close to our planet. Comets are mostly composed of ice and dust, while asteroids are rocky. According to Napier, we should fully explore the solar system in search of fragments of comets and also extremely dark bodies (dormant comets) cannot be detected with commonly available tools, but need to be tracked with infrared radiation. Need more life? All these negative aspects of travel the solar system by the densest regions of the Milky Way would have a positive side, scientists say: the possible expansion of life remote parts of the universe. It is possible, say the astronomers, that periods of collision of Earth with meteorites would allow microbial forms of life (microorganisms) abandoning the Earth, carried by the dust and stone fragments detached at impact, to populate distant parts of the universe. This idea is related to the theory of Panspermia , which says that life on Earth began thus to come in the form of microorganisms in a meteorite. Although a controversial theory, it is true that evidence of bacteria capable of surviving long periods in outer space. Chandra Wickramasinghe one of the originators of the theory (along with the astronomer Sir Fred Hoyle said in an interview in 2003 that he and his researchers had found evidence of the existence of organic molecules in interstellar dust and commentary dust in the. Although it is accepted that interstellar and commentary dust is organic in a rather high level, the question asked Wickramasinghe was then: how is that particles formed in space have the same properties as the germs?

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