The SPHERE instrument, recently installed on the VLT (Very Large Telescope), the world's most advanced optical instrument, has caught its first light. His initial photographs already show a considerable improvement in capturing the faint glow of distant exoplanets. In the image on the left, which seems to be inspired by a fantasy film, it managed to portray with exceptional clarity the ring of dust that surrounds the star HR 4796, located 220 light years from Earth , thanks to the suppression of the glare of the starlight in the center of the image.
This new tool, assembled in one of the four telescopes that make up the instrument, combines advanced techniques that, according to its developers (Institute of Planetology and Astrophysics of Grenoble in collaboration with the European Southern Observatory), will revolutionize the study of exoplanets and of circumstellar discs. SPHERE integrates state-of-the-art technology in adaptive optics, special detectors and coronography components, thus providing the highest contrast ever achieved in direct imaging of planets , surpassing even its predecessor, the NACO instrument, creator of the first image. direct from an exoplanet.
To date, only a few exoplanets have been directly imaged. Most of these planetary system neighbors have been detected using indirect techniques, such as variations in the radial velocity of the host star, or changes in the star's brightness caused by its transit. Their visual monitoring is vital, since many of them meet optimal habitability conditions.
