Students to save the Earth

Nine students from the

have developed a model spacecraft for deflecting objects falling from space.

The model has been created in response to the asteroid Apophis, which could in theory collide with Earth in 2036, and was presented at a competition organised by NASA and the American Institute of Aeronautics and Astronautics.

The initial plan would put the $353m craft into space in 2020 where it will approach the asteroid and launch two penetrating devices onto it. These will deliver equipment including a specially adapted camera, transmitter and antenna. Air bags will be used to safely deliver the equipment. Solar panels attached to the air bags will deliver power to the equipment.

The equipment will collect data on the location and composition of the asteroid and relay it back to Earth. It is considered very unlikely that Apophis will collide with Earth. However, if required, the craft will be sent to it again in 2025 and, using its gravity, will begin to divert the asteroid from its path. Due to the difference in mass between the asteroid and the spacecraft, it will not be able to divert the asteroid with enough force and will need the assistance of the Earth’s mass. Since in 2029, the asteroid is supposed to pass near the Earth, the spacecraft will use the Earth’s mass in order to divert it.

According to Dr Alexander Kogan, who guided the students, the craft will use its ion thrusters to hover 200-300m from the asteroid for four months. Using the mass of the spacecraft, combined with the effect of Earths’ gravity, the craft will pull the asteroid out of its previous path.

‘The spacecraft is what will make the difference,’ said student Lior Avital. ‘It will divert the asteroid one kilometre and with the help of the Earth, in seven years - 7,000km.’

Alternatives such as blasting the asteroid with a nuclear bomb were also considered, but the group believed the danger posed by two large asteroids or many small ones would be much greater. Diverting the asteroid by connecting powerful motors to it was also ruled out as the solution was deemed too expensive and complicated.