While there seems to be no shortage of sizeable space rocks whizzing past our planet these days, an asteroid impact with catastrophic consequences for life on Earth thankfully remains the premise of sci-fi disaster movies.
Asteroid 4660 Nereus, which is expected to pass Earth’s orbit on 11 December, is also unlikely to hit us, despite being labelled a potentially hazardous asteroid (PHA) by NASA.
Being 330 metres in diameter, which makes the asteroid taller than landmarks such as the Eiffel Tower or Chrysler Building, 4660 Nereus will approach Earth at a distance of approximately 3.9 million kilometres. And while it appears to pose no immediate threat to our planet, its absolute magnitude (18.4, which is less than 22 – one of the requirements for being classified as PHA) and the distance it approaches our planet at (less than 0.05 astronomical units – another requirement) resulted in it being regarded as "potentially hazardous."
Later in December, another asteroid measuring between 84 and 190 metres in diameter is expected to pass relatively close to Earth.