Gaia DR1 completeness within 250 pc and star formation history of the
  Solar neighbourhood
  Taking advantage of the Gaia DR1, we combined TGAS parallaxes with the
Tycho-2 and APASS photometry to calculate the star formation history (SFH) of
the solar neighbourhood within 250 pc using the colour-magnitude diagram
fitting technique. Our dynamically-evolved SFH is in excellent agreement with
that calculated from the Hipparcos catalogue within 80 pc of the Sun, showing
an enhanced star formation rate (SFR) in the past ~4 Gyr. We then correct the
SFR for the disc thickening with age to obtain a SFR that is representative of
the whole solar cylinder, and show that even with an extreme correction our
results are not consistent with an exponentially decreasing SFR as found by
recent studies. Finally, we discuss how this technique can be applied out to ~5
kpc thanks to the next Gaia data releases, which will allow us to quantify the
SFH of the thin disc, thick disc and halo in situ.
