Solar sail flotilla could intercept Apophis asteroid

The Apophis asteroid (99942) is expected to pass uncomfortably close to Earth in 2036.

But instead of nervously counting down until Apophis arrives, one French researcher believes the potentially dangerous asteroid should be intercepted by an armada of solar sail spacecraft.

According to Jean-Yves Prado of the National Center for Space Study (CNES) in France, the fleet of solar-powered ships would effectively shade Apophis from solar radiation and possibly alter its course. 

The above-mentioned plan is based on eliminating the so-called Yarkovsky effect, which occurs when an asteroid is warmed more on the sun-facing side than its far side.

This causes the flying rock to emit more thermal radiation on its near side, thereby creating a slight thrust which changes its momentum – albeit slightly. 

“It’s really a very small effect and doesn’t apply to very small asteroids because the temperature would be quite negligible, so thrust is negligible,” explained Prado.  

“It also does not apply to very large asteroids because they are too heavy. [Really], Apophis is a nice target for launching this kind of mission for 20 years from now; not too far, not too close.”

However, a number of experts have expressed skepticism over any plan that involves altering the course of Apophis, claiming that such attempts to divert the hurtling space rock would likely make matters worse.

Note: NASA astronomers currently place the chances of Apophis hitting Earth at a relatively low 1-in-250,000 chance in 2035, and a three-in-a-million chance when it approaches the planet again in 2068.