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

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

A NASA scientist has warned that thousands of city-killing asteroids could strike Earth, and there’s currently no defense humanity could use to stop them.

Astronomers do not know where thousands of “city-killer” asteroids are, Nasa’s head of planetary defence has admitted.

NASA's head of planetary defence, Dr Kelly Fast, has issued an unsettling update on thousands of ‘city-killer’ asteroids that could hit Earth.

Earth faces a significant threat from thousands of undetected asteroids capable of destroying cities. NASA's planetary ...

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 ...

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

NASA has raised red flags over growing asteroid threats that could potentially damage the Earth.To one’s surprise, astronomers are unaware of the location of thousands ...

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 ...

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

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?