Asteroid: 99942 Apophis

Originally 2004MN4, this asteroid is going to have a substantial chance of hitting the Earth in the year 2036 after a close run in 2029.

On April 13, 2029, sky-watchers will be able to get a good look at Apophis, as it makes a pass at 36,000 kilometers above Earth's surface. It will however make another pass in 2036, which may well be when it falls to Earth. At a kilometer accross, the impact would release energy on par with 850 megatons and would probably hit the Pacific Ocean, causing a 30-foot tsunami. The likelihood of this happening is astronomically high, that is to say very high for the general statistics of large object space collisions. New data gives the asteroid a 1/8000 chance to hit or .0125%.

Aside to the danger posed by the asteroid the amount that can be learned from the near miss that will occur in 2029 is incredible. The fact that it is flying so close to us means that its rotational period will change from 30 hours to 57 hours. In addition, it will also be shifting its orbit's classification as it makes the pass. At the moment is an Aten class asteroid, those which orbit Sol inside the Earth's orbit; it will change to an Apollo class asteroid when it makes its pass, that is it will become an asteroid whose orbit crosses Earth's.


Apophis is the Helenized name of Apep, the night-time nemesis of Ra. In Egyptian mythology Apophis/Apep is said to be a snake, which attempts to consume Ra when Ra crosses the underworld during the night. Eclipses are also supposed to be the work of Apophis, though Ra is ever able to cut himself from the snake's belly.

Though the asteroid itself is named not simply for the Egyptian deity, but also for the character on Stargate SG-1, of which its discoverers Dave Tholen and Roy Tucker are fans. In the show Apophis is a major recurring villain throughout the first several seasons.

In either case the danger posed by this asteroid makes the choice of name sound.