Dark Matter Hurricane

The recent releases of data from the Gaia satellite have offered us a transformational view of our galaxy. As well as informing us of the structure and evolution of the Milky Way, there are also valuable insights to be gleaned for dark matter. The incredibly accurate position and velocity information on stars in the Gaia data is leading to an expanding catalogue of the granularity of the stellar halo in the form of clumps, streams and moving groups. The recently discovered "S1 stream" is of particular note as it appears to pass directly through the Solar neighbourhood. The progenitor of S1 is a dwarf galaxy with a total mass comparable to the present-day Fornax dwarf spheroidal, so the stream is expected to have a significant dark matter component. This will inevitably lead to consequences for experiments on Earth looking to directly detect dark matter. I will discuss the current status of our knowledge of the S1 stream and the consequences for experimental searches for WIMPs and axions.