The TESS Space Mission is currently delivering new exciting exoplanetary candidates. Almost all of the new planetary candidates are sufficiently bright to be characterized from the ground. In case of Kepler Space Mission, only a part of candidates was suitable for ground-based characterization, therefore, we do not have a precise mass and radius measurements for many of the Kepler planets. However, this will also change for PLATO Space mission as the target group of the mission is a group of about a million main sequence stars brighter than 11 Vmag (see Fig. 1). The TESS and PLATO candidates will require a thorough follow-up measurements from the ground. Therefore, main scientific goals of the PLATOSPec spectrograph will be:

• determination of the stellar parameters of the candidate host stars (initial screening)
• selection of promising candidates for further follow-up with larger facilities
• Radial Velocity (RV) follow-up of gas planets to measure their mass and radius
• long term RV follow-up of selected candidates (cold Jupiters)
• spectroscopic characterization of exo-atmospheres (gas planets)
• additional science such as stellar pulsations, flaring stars and many other topics

The PLATOSPec is designed in such way that it can obtain precise RVs (approx. 5 m/s) for the core sample of the PLATO targets. The added value will be the ability of long term monitoring which is usually not possible with large facilities.

Figure 1: The Plato Space Mission will search for planets around a million brightest star. PLATOSpec will be able to follow-up the PLATO targest with an RV accuracy of at least 5 m/s for the majority of targets. Figure from Rauer et al. 2012, Experimental Astronomy, Volume 38, Issue 1-2, pp. 249-330