Exact date 'planet killer' asteroid to shoot past Earth in closest call for 125 years
![Exact date 'planet killer' asteroid to shoot past Earth in closest call for 125 years](https://i2-prod.mirror.co.uk/incoming/article33107756.ece/ALTERNATES/s615/0_Near-Earth-asteroid-artwork.jpg)
The space rock, known as 2011 UL21, is roughly the size of Mount Everest and it is classified as a "planet killer", which means it could destroy continents and cause catastrophic climate change