Stellar streams as dark‑matter detectors

Cold, thin streams of stars from disrupted star clusters and dwarf galaxies act like seismometers: small dark‑matter clumps passing nearby leave measurable gaps, wiggles, and timing shifts. Mapping those perturbations with high‑precision astrometry (e.g., Gaia) turns the Milky Way into a laboratory for the small‑scale structure of dark matter. — If stellar streams can robustly reveal dark‑matter substructure, they provide a near‑term empirical route to discriminate dark‑matter models, influence funding and policy for space missions, and shape public conversation about the nature of the dark universe.