Roger-Maurice Bonnet is the President of COSPAR.

An asteroid called Apophis will pass close to Earth on 13 April 2036. The energy released would have the equivalent of between 880 and 1480 megatons of TNT. (The 1883 eruption of Krakatoa was the equivalent of about 200 megatons.) On the positive side, scientists have calculated that there is less than a 0.003% chance of it hitting our planet.

The problem of Near Earth Objects (NEOs) and the likelihood of impacts with Earth however is a pressing concern and one that even the United Nations may decide to address. A group of former astronauts and cosmonauts say that work should begin on considering a strategy to protect humankind from Apophis and other asteroids.

The Association of Space Explorers (ASE) are planning meetings over the next two years - to be attended by diplomats, astronomers, astronauts and engineers - to draft an international treaty to address the threat. ASE has observer status at the United Nations Committee on Peaceful Uses of Outer Space (UN-COPUOS) and the treaty will be presented to the UN for adoption within a year.

Dr Bonnet will be one of the experts helping to draft the treaty.

A report entitled "Deflecting NEOs: A Pending International Challenge" was recently presented by ASE to the Scientific and Technical Subcommittee of the UN Committee on Peaceful Uses of Outer Space (UN-COPUOS). Why is there now a lot of attention paid to NEOs?

In particular, and right now, I have no real idea why there is particular attention. Obviously there has always been a threat to the planet, however minor, of collisions with Near Earth Objects (NEOs). Informal networks have been set up for a period of time now, mainly led by Italian scientists, to discuss the subject.

How could we on Earth help prevent collisions with NEOs?

There are two kinds of object which can be called NEOs and potentially could collide with Earth, asteroids and comets. Asteroids are solid, relatively slow-moving bodies and we generally know their trajectories with a high degree of accuracy. We tend to know years in advance about the potential risk to Earth - such as the asteroid called Apophis. Also there are comets which travel at high speed from far away. These objects are harder to predict but luckily the risk of collision is small. The problem with comets is that we find out about them sometimes with very little notice. Interestingly the Moon, despite being smaller, is at much greater risk than us. Our atmosphere stops a lot of incoming space material getting as far as the surface.

Why has the United Nations and particularly UN-COPUOS become involved with this issue?

That's a good question! The threat affects every living thing on Earth and life as we know it might disappear if something above a certain size collided with us. 65 million years ago a large object hit the Gulf of Mexico, probably wiping out the dinosaurs. The threat doesn't affect any one country more or less than any other country - it's a global problem. Organising internationally makes a lot of sense. In the end it might not be the United Nations that leads the way - maybe other international organisations may become important.

How did you become personally involved with the ASE initiative?

I am interested in the topic of Near Earth Objects and have written on the subject. The Association of Space Explorers, knowing my interest, approached me and invited me to take part. I must conclude that there is a lot of trouble with this subject as the press can sometimes sensationalise it. Personally, I am less interested in the fantasy this subject can cause and more in the science.