How Many Kepler Exoplanets are Expected to Have Trojan Asteroids?

A statistical search for a population of Exo-Trojans in the Kepler dataset

Authors:

Hippke et al

Abstract:

Trojans are small bodies in planetary Lagrangian points. In our solar system, Jupiter has the largest number of such companions. Their existence is assumed for exoplanetary systems as well, but none has been found so far. We present an analysis by super-stacking ∼4×104 Kepler planets with a total of ∼9×105 transits, searching for an average trojan transit dip. Our result gives an upper limit to the average Trojan transiting area (per planet) corresponding to one body of radius less than 460km at 2σ confidence. We find a significant Trojan-like signal in a sub-sample for planets with more (or larger) Trojans for periods greater than 60 days. Our tentative results can and should be checked with improved data from future missions like PLATO2.0, and can guide planetary formation theories.