The date for Armageddon has been set, and it's not going to happen in 2012.
In 2004, NASA scientists announced that there was a chance that Apophis, an asteroid larger than two football fields, could smash into Earth in 2029. A few additional observations and some number-crunching later, astronomers noted that the chance of the planet-killer hitting Earth in 2029 was nearly zilch.
Now Russian scientists estimate Apophis will collide with Earth on April 13, 2036. These reports conflict on the probability of such a doomsday event, but the question remains: How scared should we be?
“Technically, they’re correct, there is a chance in 2036 [that Apophis will hit Earth]," said Donald Yeomans, head of NASA’s Near-Earth Object Program Office. However, that chance is just 1-in-250,000, Yeomans said.
NASA was quick to discount Russia's fears, however. “The situation is that in 2029, April 13, [Apophis] flies very close to the Earth, within five Earth radii, so that will be quite an event, but we’ve already ruled out the possibility of it hitting at that time,” Yeomans told Life’s Little Mysteries, Space.com's sister site.
An artist's concept of a catastrophic asteroid impact with the early Earth. NASA and other space agencies are discussing how would we prevent such asteroids collisions ... and they have some far-out ideas. slideshow
Russia is considering sending a spacecraft to a large asteroid to knock it off its path and prevent a possible collision with Earth. Just how would we prevent asteroids from colliding with Earth?
"No one should worry. Between Mars and Jupiter, we have an asteroid belt. There's all the asteroids going near the sun, and these objects are coming near the earth all the time," Tim Hill, space manager at the Museum of Science and Industry in Tampa, told MyFoxTampaBay.
“On the other hand, if it goes through what we call a keyhole during that close Earth approach … then it will indeed be perturbed just right so that it will come back and smack Earth on April 13, 2036,” Yeomans said.
The Russian scientists are basing their predictions of a collision on the chance that the 900-foot-long (270 meters) Apophis will travel through just such a keyhole, called a gravitational keyhole, as it passes by Earth in 2029. The gravitational keyhole they mention is a precise region in space, only slightly larger than the asteroid itself, in which the effect of Earth's gravity is such that it could tweak Apophis' path.
The chances of the asteroid going through the keyhole, which is tiny compared to the asteroid, are “minuscule,” Yeomans added.
The more likely scenario is this: Apophis will make a fairly close approach to Earth in late 2012 and early 2013, and will be extensively observed with ground-based optical telescopes and radar systems. If it seems to be heading on a destructive path, NASA will devise the scheme and machinery necessary to change the asteroid’s orbit, decreasing the probability of a collision in 2036 to zero, Yeomans said.
There are several ways to change an asteroid’s orbit, the simplest of which is to run a spacecraft into the hurtling rock. This technology was used on July 4, 2005, when Deep Impact smashed into the comet Tempel 1.
The 99942 Apophis asteroid which caused great concerns way back in December 2004 was once again revived as Russian scientists reported that it could hit the Earth on April 13, 2036. In fact, Donald Yeomans of NASA confirmed that this may happen and gave odds of 1 in 250,000.
With a diameter of 270 meter and measuring approximately the size of two football fields, the asteroid was originally predicted that may hit Earth in 2029. However, after careful observations, that date was moved to 2036.
Still, 2036 is just 25 years from now. Professor Leonid Sokolov from St. Petersburg State University gave a calming statement that the 99942 Apophis asteroid would most likely disintegrate before hitting Earth if it passed a gravitational keyhole in 2029.
In case it would really happen, NASA gave an estimate that it may cause a damage to the Earth equivalent to 510 megatons of TNT. To prevent it from hitting the Earth, NASA already devised a plan of constructing a machinery to alter its orbit. Other proposed method of deflecting the asteroid as studied and proposed by NASA, European Space Agency and various research groups include kinetic impact, nuclear bomb, and gravitational tractor.
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