A History of meteorite impacts
After the meteorite shower in Russia this morning, lot of questions are still up in the air. Did this happened before? It's related with the asteroid that will pass near Earth this evening? How often do meteors hit the planet?
According to the Russian Academy of Sciences, the meteorite that entered the earth’s atmosphere today weighed 10 tons and was travelling at speed of at least 54,000kph, and shattered between 30 to 50km above ground. However, it wasn't the only meteorite impact on Earth's history.
The most damaging impact occurred 66 million years ago, when a meteorite caused the extinction of the dinosaurs. Geological evidence shown that a giant meteor about six miles wide smashed into the Yucatan Peninsula and set off volcanic eruptions, massive earthquakes and tsunamis.
This never happened again, but according to Discovery Channel, scientists are keeping a close eye on a big asteroid that may pose an impact threat to Earth in 2040.
The space rock called 2011 AG5, is about 140 meters wide and it may come close enough to Earth that some researchers are calling for a discussion about how to deflect it, the TV channel published one year ago.
Nevertheless, Detlef Koschny of the European Space Agency's Solar System Missions Division in Noordwijk, The Netherlands, said that “the confidence in these calculations is still not very high."
Paying attention to History, there are some unsolved issues related with meteorites. For instance, scientists believe that the Black Stone in Mecca is a meteorite, but because of its religious significance, it has not been tested, nor is it ever expected to be studied.
One of the most famous meteorite strikes happened in 1908 also in Russia, and it's know as the Tunguska event. Despite the object exploded three to six miles above Earth's surface, it is still referred to as an impact. According to scientists, if this meteor had been almost anywhere else in the world, there would have been at least one city destroyed.
After the event, many conjectures came up, from a Natural H-bomb to a black hole andaliens invasion. A science fiction story, written by Alexander Kazantsev in 1946, claims that Tunguska event was the result of the activities of extraterrestrial beings, including an exploding alien spaceship.
NASA's Near Earth Object Project lists potential future Earth impact events based on currently available observations collected by Sentry, a highly automated collision monitoring system. It continually scans the most current asteroid catalogue for possibilities of future impact with our planet over the next 100 years.
Between 2015 and 2099 NASA says that will be 30 potential impacts, which have low potential probability's figures. In the other hand, the period in which more probably a meteor will hit the Earth is 2095-2110.
Therefore, we don't have to be worried about the asteroid that this evening will pass near the Earth and just enjoy its view, with binoculars of course. NEW EUROPE ON LINE
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