While scientists are confident a large asteroid crashed into Earth approximately 65 million years ago, leading to the extinction of dinosaurs and some other life forms on our planet, they do not know exactly where the asteroid came from or how it made its way to Earth. A 2007 study using visible-light data from ground-based telescopes first suggested the remnant of a huge asteroid, known as Baptistina, as a possible suspect. According to that theory, Baptistina crashed into another asteroid in the main belt between Mars and Jupiter about 160 million years ago. The collision sent shattered pieces as big as mountains flying. One of those pieces was believed to have impacted Earth, causing the dinosaurs’ extinction.

Last week Chinese scientists wanted to divert an asteroid away from Earth. This week, they want to pull one into orbit around the Earth. What’s possible objections could anyone have to this idea?

The asteroid, called 1999 RQ36, has a 1-in-1,000 chance of actually hitting the Earth at some point before the year 2200, but is most likely to hit us on 24th September 2182. It was first discovered in 1999 and is more than 1,800 feet across. If an asteroid of this size hit the Earth it would cause widespread devastation and possible mass extinction. And scientists say that any attempt to try and divert the asteroid will have to take place more than 100 years before it is due to hit to have any chance of success.