You may have heard of the Trojans, two vast swarms of asteroids that lead and trail Jupiter on its orbit around the Sun.

But the king of the planets doesn’t hold a monopoly on Trojan asteroids. The physics that gives rise to the formation of these distinctive collections of ancient rocks is the same for all planets – including Earth.

While the existence of Earth Trojans had been theorised for many years, the first direct observation of one was confirmed just over a decade ago. Since then, no second Earth Trojan