The 99942 Apophis asteroid, named after an Ancient Egyptian deity, has a 371 m diameter and has a near-Earth trajectory that brings it close to Earth each pass around the sun. Apophis gained notoriety in 2004 when scientists calculated it had a 2.7% change of impacting the Earth in 2029.
More recently, more in-depth calculations, taking into account the Yarkovsky Acceleration effect of the sun, have determined an Apophis collision is much more likely than first thought.
Indeed, the new calculations show the asteroid poses a greater threat than originally believed, and that the chances of an Earth-impact, rises significantly in 2068.
Engineers around the globe are working on ways of deflecting and mitigating potential impacts with the Earth. Concepts range from gravitation tugs to kinetic impactors. As a species, it is a mathematical certainty of when, not if there will be another extinction level impact, for which we must prepare or face the same fate as the dinosaurs.
There are more undetected bodies in and around our Solar System than we have found to date. So while we must prepare for those we know about, including Apophis collision outcomes, we also have to prepare regardless, because at some point, our very survival will count on it.