Mayan prophecy looming over Earth? This time it is not the usual presumed prediction of the pre-Columbian people, but a scientific fact, incontrovertible, or at least much more credible than the poorly certified allusions on the date of December 21, 2012.
NASA does not provide dates, we can breathe a sigh of relief, but an increasingly threatening danger emerges from its latest census of space: they are well 4.700 asteroids that gravitate in the universe and that could be susceptible to colliding with the Earth and causing catastrophes. This is due to their relatively short distance (within a radius of less than 8 million kilometres, ie 20 times the Earth-Moon distance), and their consistency, so they would not disintegrate upon contact with the Earth's atmosphere.
According to the study, carried out by NASA's Jet Propulsion Laboratory thanks to the Wide-field Infrared Survey Explorer (WISE) infrared space telescope, and which will be published in the next issue of the Astrophysical Journal, the 4.700 asteroids that hang around the "periphery" of the Earth are all no less than 100 meters in diameter.
The parameter may seem small when compared to that of the asteroid - with a diameter of 10 kilometers - which in the Cretaceous it was suspected of having caused the disappearance of dinosaurs and many other living species. But in 1908 an unidentified celestial body (meteorite or comet) of just 20 meters in diameter exploded over the area of central Siberia, causing the destruction of over 300 square km of forest. And among the fantastic 4.700 surveyed by NASA, this kind of bodies are not even taken into consideration.
To see more clearly, however, NASA is already working on one exploratory mission, robotic or perhaps even human, by 2025. Hoping that, Maya - and asteroids - permitting, it's not already too late.
