A new study published in Astronomy & Astrophysics unveils a powerful way to determine the size of dark matter haloes—the massive, invisible structures that host galaxies—by simply measuring how large galaxies appear in deep astronomical images. Researchers Ignacio Trujillo and Claudio Dalla Vecchia, from the Instituto de Astrofísica de Canarias (IAC) and the Universidad de La Laguna (ULL), demonstrate that galaxy size can serve as a precise proxy for halo size, offering measurements up to six times more accurate than previous methods. Using the cutting-edge EAGLE cosmological simulations

This Saturday, 29 March 2025, the Instituto de Astrofísica de Canarias (IAC) was able to follow the partial solar eclipse from the Teide Observatory in Tenerife. Although subtle to the naked eye, this eclipse was used by the IAC's outreach team to raise awareness of the phenomenon among a group of people from the ‘Friends of the IAC’ programme and IAC staff. At the same time, an observation was also made from the IAC Headquarters in La Laguna, which could be seen live on the centre's YouTube channel. The eclipse began at 09:14 UT and ended at 10:56 UT, with its maximum at 10:03 UT. For just

The Instituto de Astrofísica de Canarias (IAC) invites the public to visit the Teide Observatory (Izaña, Tenerife) during the weekend of 21 and 22 June, coinciding with the week of the summer solstice. The activity is part of its Open Days, a free science outreach initiative organised by the Observatory itself together with the IAC's Scientific Communication and Culture Unit (UC3). Over two days, those attending will be able to tour some of the most important scientific facilities at the centre, learn how they work from the technical and research staff, and make live solar observations. Each