The Fifth Catalogue of Nearby Stars (CNS5) aims to provide the most
volume-complete sample of stars in the solar neighbourhood. The CNS5
is compiled based on trigonometric parallaxes from Gaia EDR3 and
Hipparcos, and supplemented with astrometric data from Spitzer and
ground-based surveys carried out in the infrared. The CNS5 catalogue
is statistically complete down to 19.7 mag in G-band and 11.8 mag in
W1-band absolute magnitudes, corresponding to a spectral type of L8.
Continuous updates of observational data for nearby stars from all
sources were collected and evaluated. For all known stars in the 25 pc
sphere around the Sun, the best values of positions in space,
velocities, and magnitudes in different filters are presented.
This is a clean and well characterised catalogue of objects within 100pc of
the Sun from the Gaia early third data release. We characterise the
catalogue using the full data release, and comparisons to other catalogues
in literature and simulations. For all candidates (measured parallax <
8 mas), we calculate a distance probability function using Bayesian
procedures and mock catalogues for the prediction of the priors. For each
entry using a random forest classifier we attempt to remove sources with
spurious astrometric solutions.
This results in 331312 objects that should contain at least 92% of stars
within 100 pc at spectral type M9.
GCNS comes with several auxiliary tables, in particular lists of
resolved stellar systems, of known neary stars not found in eDR3 and
of candidates of Hyades and ComaBer cluster members.
