Artist’s animation of Trojan debris clouds

This animation shows a planet and two clouds of debris at the so-called Lagrangian zones in the planet’s orbit, all moving around a central star. Lagrangian zones are two extended regions in a planet’s orbit where the combined gravitational pull of the star and the planet can trap material. These regions can be occupied by Trojans, which are rocky bodies in the same orbit of a planet.

In theory, these Trojans could be in both these regions, but in the PDS 70 system astronomers have so far detected only one cloud in the orbit of the exoplanet PDS 70b. The detected cloud could point to an existing Trojan planet in the same orbit as PDS 70b, or a world in the process of forming.