He said that such comets had occurred consistently every 50 or 60 million years. With the last happening around 65 million years ago.
But his biggest concern was that if such an object was to hit earth, we have no way to defend ourselves.
With the current tech, NASA needs to see the body almost seven years before impact to have any realistic chances of evading the impact.
"The biggest problem is there's not a hell of a lot we can do about it at the moment," Nuth said. "If you look at the schedule for high-reliability spacecraft and launching them, it takes five years to start a satellite."
But on the bright side, NASA has an incredibly strong telescope that has verified that there is no comment on earth path for at least the next one hundred years.
But they still warned that there might be some asteroids that are blinded from NASA especially in the sun's directions that may sucker punch earth.
However, Nuth insisted the best ways to protect Earth from such hazards was by having space craft's on standby instead of building them when need be.
He said that NASA should have a nuclear warhead spacecraft to blow up such asteroids. But this may not be the most efficient what as the results are not known. He suggested having a cannon like a space ship to deflect the approaching bodies may be more viable.