Last Tuesday, November 8, 2011, an asteroid the size of an aircraft carrier whistled past Earth at a distance of 202,000 miles away – just inside the moon's orbital distance. For those capable of grasping astronomical distances, this is what they would probably describe as a near miss. The Asteroid's path has been the closest for an asteroid since 1976 and won't be repeated until 2028.
Known as 2005 YU55, the asteroid was discovered on December 28, 2005 and has been tracked by NASA and scientists worldwide to determine the possibility of an Earth impact. NASA remained confident that the asteroid posed no unusual level of danger as it passed near Earth. An Earth impact would have caused 70ft-high tsunami had it landed in the ocean.
The figure below from NASA Jet Propulsion Laboratory shows a few asteroids who flew by (and who will fly by) our planet Earth. On June 26, 2028, asteroid 2001 WNS will fly by Earth at a distance much closer than that of 2005 YU55, while on April 13, 2029, asteroid Apophis will fly by within the orbits of Earth's geosynschonous satellites (which orbit earth at a distance of approximately 22,236 miles). This will make Apophis visible to the naked eye and will make the flyby an extremely close encounter.
Incidentally, in Egyptian mythology, Apophis was the ancient spirit of evil and destruction, a demon that was determined to plunge the world into eternal darkness. Apophis was viewed as the greatest enemy of the sun-god Ra, and thus was given the title Enemy of Ra.
No worries though, Apophis won't impact Earth and we won't be plunged in eternal darkness. The fates of the Earth’s man-made satellites remain unknown though... We have a lot orbiting up there and I doubt if scientists or astronomers have computed the probability of Apophis hitting any one of them.
Space junk – what goes up must come down. Filipinos have a saying that goes to the same effect: “Basurang itinapon mo, babalik din sa’yo”.
What would happen if Apophis hits any one of these space junk? It’s anybody’s guess now…
