Earth faces a significant threat from thousands of undetected asteroids capable of destroying cities. NASA's planetary defence chief warns that current systems cannot reliably stop these 'city-killers ...

A NASA planetary defense officer warns thousands of near-Earth asteroids capable of destroying a city remain undetected.

"We don’t know where they are,” said NASA’s planetary defense officer Kelly Fast at the AAAS conference in Arizona this week.

“What keeps me up at night is the asteroids we don’t know about," said NASA's planetary defense chief.

NASA officials warn thousands of undetected “city killer” asteroids may be circling near Earth. With limited deflection tools ready, are we prepared if one suddenly shifts onto a collision course?

Scientists discussed the threat of asteroids at a recent conference in Phoenix. Here's what they said.

Space agencies maintain that global cooperation and sustained investment are vital to planetary defence. While the DART ...

She’s worried about the a-rock-alypse. A planetary defense expert is warning that humanity is defenseless against up to 15,000 undetected near-Earth asteroids that have the potential to take out a ...

NASA planetary defense experts warn that up to 15,000 undetected asteroids could devastate a major city on Earth.

NASA has warned that about 15,000 mid-sized “city-killer” asteroids near Earth remain undiscovered, with the potential to cause regional devastation, as scientists say no deflection mission is ready ...

EARTH cannot defend itself against the thousands of “city killer” asteroids that are zooming around space near our planet, Nasa chiefs warn. They reckon there are about 15,000 undetected ...