Speaker
Description
If dark matter is sufficiently light, it can coherently scatter with macroscopic objects, greatly enhancing its scattering cross-section. This allows the wind of dark matter through our Solar System to apply sizeable forces on objects. It turns out that the ideal size of object for which the coherent effect is maximized but the acceleration is still large is in the 1-10 cm range. This motivates us to look for observational effects in the dense planetary ring systems in which these particles sizes dominate. We find that the dark matter creates a drag force on Saturn's rings which can be larger than the equivalent effect from Solar radiation, and which would affect smaller particles more than larger ones. It may have been possible to use this to constrain the dark matter---however, as it turns out, there actually is a yet-unexplained mass segregation which has been observed in Saturn's main rings.