November 15, 2024. Tracking Apophis 1. Introduction

Apophis (99942 Apophis)is a near-Earth asteroid, discovered in 2004 measuring 450 meters by 170 meters which caused alarm because of the possibility of colliding with Earth. When discovered, the first calculations showed that there was a 2.7% chance of collision in April 13, 2029, however, subsequent calculations have located that risk at a much safer place.

Apophis orbits the Sun with a period of 323.7 days. It approaches Earth roughly every 7.75 years and during each of those approaches the orbit is forced to vary due to the gravitational pull of earth

Asteroid image obtained from Wikimedia Commons. It shows asteroid Ida as taken by the Galileo spacecraft. No Copyright. This file is in the public domain in the United States because it was solely created by NASA. NASA copyright policy states that "NASA material is not protected by copyright unless noted.