Haze Formation on Triton

Abstract The largest moon of Neptune, Triton, possesses a cold and hazy atmosphere. Since the discovery near-surface haze layer during Voyager fly in 1989, formation mechanism has not been investigated detail. Here we provide first microphysical model on Triton. Our solves evolution both size porosity distributions particles self-consistent manner. We simulated sphere aggregate hazes with without condensation C 2 H 4 ice. can grow into fractal aggregates mass-equivalent sizes ∼0.1–1 μ m dimensions D f = 1.8–2.2. ice-free cannot simultaneously explain UV visible observations 2, while including ices provides two better solutions. For ice aggregates, required total mass flux is ∼2 × 10 −15 g cm −2 s −1 . icy scenario, column-integrated production rate ∼8 , ∼6 −17 occultation at short wavelengths, <0.15 m, may slightly favor aggregates. Observations optical depth degree forward scattering should be able to distinguish whether Triton’s are spheres or future Triton missions.