In this white paper, we propose an upgrade to the Very Large Telescope Interferometer (VLTI) consisting of the addition of a new 8m Unit Telescope (UT5). The primary goal of this upgrade is to optimise the VLTI for exoplanet detection by creating four additional baselines of approximately 200m oriented toward the north-west. The inclusion of this telescope would reduce the inner working angle and improve the achievable contrast of the VLTI, thereby enabling the detection of mature exoplanets in reflected light.
@article{arxiv.2512.17026,
title = {Exoplanets in reflected starlight with dual-field interferometry and a fifth Unit Telescope at VLTI},
author = {Óscar Carrión-González and Sylvestre Lacour and Mathias Nowak},
journal= {arXiv preprint arXiv:2512.17026},
year = {2025}
}
Comments
White paper submitted to ESO's "Expanding Horizons: Transforming Astronomy in the 2040s" call. 4 pages; 3 figures