Clouds, Streams and Bridges. Redrawing the blueprint of the Magellanic
  System with Gaia DR1
  We present the discovery of stellar tidal tails around the Large and the
Small Magellanic Clouds in the Gaia DR1 data. In between the Clouds, their
tidal arms are stretched towards each other to form an almost continuous
stellar bridge. Our analysis relies on the exquisite quality of the Gaia's
photometric catalogue to build detailed star-count maps of the Clouds. We
demonstrate that the Gaia DR1 data can be used to detect variable stars across
the whole sky, and in particular, RR Lyrae stars in and around the LMC and the
SMC. Additionally, we use a combination of Gaia and Gale to follow the
distribution of Young Main Sequence stars in the Magellanic System. Viewed by
Gaia, the Clouds show unmistakable signs of interaction. Around the LMC, clumps
of RR Lyrae are observable as far as ~20 degrees, in agreement with the most
recent map of Mira-like stars reported in Deason et al (2016). The SMC's outer
stellar density contours show a characteristic S-shape, symptomatic of the
on-set of tidal stripping. Beyond several degrees from the center of the dwarf,
the Gaia RR Lyrae stars trace the Cloud's trailing arm, extending towards the
LMC. This stellar tidal tail mapped with RR Lyrae is not aligned with the
gaseous Magellanic Bridge, and is shifted by some ~5 degrees from the Young
Main Sequence bridge. We use the offset between the bridges to put constraints
on the density of the hot gaseous corona of the Milky Way.
