[ELT, @deZeeuw2014] will have unprecedented capabilities for detailed studies of the atmospheres of terrestrial planets, and the interpretation of the results will require an accurate mass measurement (e.g., @Batalha:2019).

The Transiting Exoplanet Survey Satellite (TESS) [@Ricker2015] started scientific operations in July 2018, aiming to detect transiting planets around bright and nearby stars – bright enough for Doppler mass measurement to be feasible. For this task, TESS surveys about 85% of the sky during the Prime Mission. The survey covering the southern ecliptic hemisphere is now complete, and the northern survey is underway. Each hemisphere is divided into 13 rectangular sectors of $96\degree \times 24\degree$ each. Each sector is continuously observed for an interval of 27-days, with a cadence of 2 minutes for several hundred thousand pre-selected stars deemed best suited for planet searching. Additionally, during the TESS Prime Mission, the Full Frame Images – the full set of all science and collateral pixels across all CCDs of a given camera – are available with a cadence of 30 minutes. M dwarfs are of special interest because the transit and radial-velocity signals of a given type of planet are larger for these low-mass stars than they are for Sun-like stars. In 