Asteroid sharing Earth’s orbit discovered – could it help future space missions?

Where 2020 XL5 would appear in the dawn sky if we could see it with the naked eye from Chile. NOIRLab/NSF/AURA/J. da Silva, CC BY-NC-SA

Research has shown that the Earth trails an asteroid barely a kilometre across in its orbit about the Sun – only the second such body to have ever been spotted. It goes round the Sun on average two months ahead of the Earth, dancing around in front like an excited herald of our coming.

This object, known as 2020 XL₅, was first spotted in December 2020 using Pan-STARRS telescopes on the summit of Haleakala on the Hawaiian island of Maui. But determination of its orbit required follow-up observations using the 4.1-metre SOAR (Southern Astrophysical Research) telescope in Chile.