In grappling with the threat of doomsday rocks from outer space, Hollywood has always been far ahead of the US government, cranking out thrillers full of swashbuckling heroes, rockets and nuclear blasts that save the planet. Now Washington is catching up.
On Wednesday, the nation’s agencies that build civilian rockets and nuclear arms sealed an agreement to start working together on planetary defence. The goal is to learn how to better deflect comets and asteroids that might endanger cities and, in the case of very large intruders, the planet as a whole.
“Often, these agencies focus on their own pieces of the puzzle, so anything that brings them together is a good thing,” said Bruce Betts, director of science and technology at the Planetary Society, a nonprofit group.
Comets and asteroids are part of the cosmic rubble left over from the birth of the solar system. Comets, made of dirty ice, visit Earth’s neighbourhood only when knocked loose from their home orbits beyond Pluto. That makes their movement somewhat unpredictable. Asteroids, made of rock, fly mostly in a belt between Mars and Jupiter. Their orbits can be calculated with great precision if astronomers can spot the dim objects. Rocky debris rains down steadily on Earth, mostly as dust grains and tiny pebbles. But every once in a while a tumbling giant, miles wide, such as the one thought to have done in the dinosaurs, zooms past the planet.
In 2013, this threat gained new credibility after a 7,000-tonne rock exploded over the Russian city of Chelyabinsk, injuring 1,500 people, mainly as shards flew from shattered windows.
The two agencies — Nasa and the National Nuclear Security Administration — have long studied such threats on their own. They have surveyed the cosmic debris, designed rocket interceptors and run supercomputer simulations to see if a nuclear blast could nudge a large asteroid off course. In interviews, federal officials and private experts said the new agreement would deepen expert cooperation and governmental planning, ultimately increasing the chances of a successful deflection.