Shan Mignot

TL;DR: Gaia as discussed by the authors is a cornerstone mission in the science programme of the European Space Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach.

TL;DR: The 4MOST project as mentioned in this paper proposes a wide-field (3 square degree, goal >5 square degree), high-multiplex (1500 fibres, goal 3000 fibres) spectroscopic survey facility for an ESO 4m-class telescope.

TL;DR: An overview of the 4MOST systems: optomechanical, control, data management and operations concepts; and initial performance estimates are provided.

TL;DR: In this article, the first parallax measurements of the primary standard candles of the cosmological distance ladder, that involve astrometry collected by Gaia during the initial 14 months of science operation, are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS).

TL;DR: 4MOST as discussed by the authors is a wide-field, high-multiplex spectroscopic survey facility under development for the VISTA telescope of the European Southern Observatory (ESO).