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

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 ...

The National Aeronautics and Space Administration (NASA) has issued a stern warning after the agency’s head of planetary ...

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.

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

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

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?

Around 15,000 mid-sized asteroids, known as 'city-killers', are unaccounted for as they zoom around space close to planet ...

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 ...

An experiment on board the ISS tested the use of microorganisms to mine asteroids in the microgravity environment.