Planet Earth is effectively defenceless in the face of a “dinosaur-killer” asteroid strike, a Nasa scientist has warned. And the planet is overdue for an extinction-level event involving a giant space object – such as an asteroid or comet – following a number of close encounters over the last 20 years, Dr Joseph Nuth said.
Large objects from outer space that could cause mass extinctions have tended to hit Earth about 50 to 60 million years apart. The dinosaurs were wiped out 66 million years ago by an asteroid that struck what is now the Gulf of Mexico.
Dr Nuth, speaking at Nasa’s Goddard Space Flight Centre in San Francisco, said that if a potentially dangerous object was on a crash-course with our planet “there’s not a hell of a lot we can do about it at the moment”, according to The Guardian.
Dr Cathy Plesko, of Los Alamos National Laboratory, told the Guardian that humans could deflect an Earth-bound asteroid or comet with either a nuclear warhead or a “kinetic impactor, which is basically a giant cannonball”.