Fortuna and Chisari 2025, CC BY-NC-4.0

An artistic rendering of the intrinsic alignments of galaxies embedded in the large-scale structure of the Universe. Different signals contribute to the overlap alignment of shapes relative to the density field: the alignment of central galaxies with their haloes, the alignment of central galaxies relative to one another, the alignment of satellites within the halo and with the central shape, and the potential alignment of galaxies with filaments. This also leads one to hypothesize about the presence of an alignment aroundvoids.

An artistic rendering of the distorted path of photons through the large-scale structure. This phenomenon, which distorts observed galaxy shapes in the tangential direction around matteroverdensities, is known as gravitational lensing. Credit: Fortuna and Chisari (2025), CC-BY-NC 4.0, adapted from Fortuna and Chisari (2022), CC-BY-NC 4.0

From “A rising tide: intrinsic alignments since the turn of the millennium”, a review by Elisa Nora Chisari.

Astron Astrophys Rev (2025) 33:5

https://doi.org/10.1007/s00159-025-00161-8