What happens if two bits of space junk actually collide?

On 22 September, the three astronauts serving aboard the International Space Station (ISS) were ordered to shelter near an escape craft in the Russian segment of the station. Nasa had detected a large piece of space debris heading towards them and initiated emergency thrusters to avoid what it called a “possible conjunction” with the object.

It was the third time since January that the space station had been forced into an unscheduled manoeuvre, and once again highlighted the ever-growing issue of rogue debris in Earth’s orbit.

Earlier this week, space junk tracker LeoLabs issued a warning that another major collision could be about to take place.

Part of a discarded Chinese rocket and a decommissioned Soviet satellite were on course to pass within 25 metres of each other, with a 10 per cent probability of collision. Their combined mass of 2,800kg, together with a relative velocity of 53,000km/h, meant any collision would be catastrophic.