Abstract

Stellar signals in radial-velocity measurements currently limit the detection of Earth-twins using Doppler spectroscopy.To investigate possible ways for correcting stellar signals we have built a solar telescope to feed full-disk sunlight into the HARPS -N spectrograph, the nowadays most precise planet hunter. This setup enables observation of the Sun as-a-star with long-term sub meter-per-second precision. We can then use Solar Dynamic Observatory (SDO) images to link any radial velocity perturbation with physical changes on the solar surface.

During this talk, I will present the first year of data. With observations of the Sun every possible day for a few hours, this data set represents our best chance of understanding deeply stellar signals, to test the best observational strategies to look for exoplanets, and to find correction techniques to mitigate the impact of stellar signals.