An asteroid called Apophis was discovered in 2004. It was immediately considered one of the most dangerous asteroids for our planet. The scientists who discovered it stated that it could collide with Earth in 2029.
On April 13, 2029, Apophis will approach Earth very closely. However, the researchers winnowed out the possibility of a collision after detailed calculations. After that, scientists also calculated that there is no risk of collision of the asteroid with our planet in 2036 as well.
Until recently, there was the possibility of a collision in 2068. However, on March 5, when Apophis flew at a distance of 17 million kilometers from our planet, NASA conducted a study that indicated that any possibility of a collision in 2068 and much later is of no risk, too. Davide Farnocchia of NASA's Center for Near-Earth Object Studies, said:
“A 2068 impact is not in the realm of possibility anymore, and our calculations don't show any impact risk for at least the next 100 years. With the support of recent optical observations and additional radar observations, the uncertainty in Apophis' orbit has collapsed from hundreds of kilometers to just a handful of kilometers when projected to 2029.”
NASA's calculations were performed using a 70-meter antenna at the Deep Space Network's Goldstone Deep Space Communications Complex in southern California, and the 100-meter Green Bank Telescope in West Virginia. Goldstone received the signal, and Green Bank performed a "bistatic experiment" that doubled the strength of the received signal.
Apophis has a shape similar to peanuts, and its diameter is more than 200 meters. On April 13, 2029, it will pass at a distance of 32 thousand kilometers from the Earth's surface, which is less than the distance of geosynchronous satellites. At this time, residents of the Eastern Hemisphere will be able to see the asteroid without the aid of a telescope or binoculars.