The instrument

To capture and study the light emitted by the Sun, PoET includes the design of a dedicated solar telescope to interface with the ESPRESSO (Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations) spectrograph, installed in the VLT Observatory, ESO (Chile). Funded by the FIERCE project (FInding Exo-eaRths: tackling the ChallengEs of stellar activity) lead by the IA, PoET is currently in development.

It’s preliminary design features PoET as a two‑telescope system. The pointing telescope will be used to integrate the light from the full disk of the Sun, while the main telescope will be able to spatially resolve the solar disk. With this configuration we expect that spectra of small sections at the Sun’s surface will be obtained with different spatial resolution, ranging from 1 arcsecond up to 1 arcminute. This telescope configuration will allow us to obtain, simultaneously, disk integrated (sun-as-a-star) and disk resolved observations.

Spectra of the Sun as acquired by PoET will be obtained in ESPRESSO’s Ultra-High Resolution mode (R~220000, covering the wavelength range from 380 to 780 nm in one single shot), allowing to resolve spectral lines.









The project is undergoing the final design and is expected to see first light in Q2 2025.