Demonstration of the Existence of Dark Matter
Demonstrate the existence of dark matter as a non-baryonic component of the universe distinct from ordinary matter by providing conclusive observational or experimental evidence beyond gravitational inferences used in cosmology.
References
Those two properties led to the hypothesis that the universe must be decelerating in its expansion owing to the mutual gravitational attraction of all the matter in the universe, which we now assume are of two different kinds, baryonic matter and the Dark Matter, where the existence of Dark Matter still has to be demonstrated29.
                — A Civilian Astronomer's Guide to UAP Research
                
                (2411.02401 - Villarroel et al., 17 Oct 2024) in Section 7.1