The cool surfaces of binary near-Earth asteroids

► Binary near-Earth asteroids (NEAs) have higher thermal inertia than typical NEAs. ► Slow-rotator NEAs also have higher thermal inertia than typical NEAs. ► Implication: relative lack of fine regolith on binary and slow-rotator NEAs. ► Implication: a binary-formation process involving regolith movement. ► This supports formation of binary NEAs through YORP-induced disruption.