SPHERE: a 'Planet Finder' instrument for the VLT

TLDR

Direct detection and spectral characterization of exoplanets is exciting yet challenging because the host star outshines the planet by more than 12.5 magnitudes at small angular separations within the seeing halo. The paper presents the science objectives of the SPHERE instrument. It describes the conceptual design and expected performance of SPHERE, a planet‑finder optimized for high contrast close to the central star.

Abstract

Direct detection and spectral characterization of extra-solar planets is one of the most exciting but also one of the most challenging areas in modern astronomy. The challenge consists in the very large contrast between the host star and the planet, larger than 12.5 magnitudes at very small angular separations, typically inside the seeing halo. The whole design of a "Planet Finder" instrument is therefore optimized towards reaching the highest contrast in a limited field of view and at short distances from the central star. Both evolved and young planetary systems can be detected, respectively through their reflected light and through the intrinsic planet emission. We present the science objectives, conceptual design and expected performance of the SPHERE instrument.