Brosch and Adi Zitrin, his MSc student, identified a possible dark matter filament relatively close to the Milky Way and the Local Group in the form of a chain of galaxies in the local void . The reality of this galaxy filament, and the identification of another, shorter filament in the same neighborhood, was confirmed by McQuinn et al. (2014). Together with another student, he showed that many near-Earth asteroids are probably only "rubble piles" so that attempts to mitigate possible future impacts by such asteroids using exploding nuclear devices might not be successful.