The only way we, as humans, are going to survive and have a good opportunity to destroy Asteroid Apophis is if it does not go through the "keyhole". The "keyhole" is a gravitational field which allows the asteroid to pass right by the Earth. Scientists are concerned that if the asteroid goes through the "keyhole", it could come back seven years later during its next orbit. This gravitational "keyhole" will tear up some of the exterior of the asteroid, changing its shape and characteristics, and, in turn, affect its impact. Scientists are planning to send probes to calculate the acceleration, the exact length, diameter, and the substance of the asteroid.
There is said to be a 1:1000 chance of the asteroid hitting the Earth in 2036 because of the Sun's gravitational force pulling the asteroid back to Earth. With this information, scientists will be able to create a more direct course of action, such as ramming the asteroid with a satellite or sending a team of astronauts to try to destroy the asteroid. There is still much to consider about how the Earth is to defend itself against Asteroid Apophis.
Image of an Asteroid gliding through space. Picture from www.sanfranciscosentinel.com