Delving into development and policy now:
Astrophysics > Instrumentation and Methods for Astrophysics arxiv.org/abs/2512.14785
[Submitted on 16 Dec 2025]
de León, J. Pinilla-Alonso, N. Tanga, P. et al. Why the Northern Hemisphere Needs a 30-40m Telescope and the Science at Stake: from Interstellar Visitors to Planetary Defence
White Paper submitted to “ESO Expanding Horizons: Transforming Astronomy in the 2040s”
We have a Vera Rubin Observatory. We have an Extremely Large Telescope (under construction). We even have a Giant Magellan Telescope in optical readiness, final mechanical design, and site construction, too. All these have in common a Southern-Hemisphere siting. Dare we leave a Northern-Hemisphere gap? de León et al. say no, for multiple reasons. Aside from general astronomy, this white paper specifically gives the arguments regarding condensed-matter, small-body astronomy. 3I/ATLAS, anyone? And since large telescopes take years of planning and construction ( let alone money), we’d better get on the job. TMT, anyone?