The irrefutable existence of dark matter was established just over half a century ago when astronomer Vera Rubin studied the orbits of stars and gases in galaxies. Today, we understand that it constitutes 85% of the universe’s matter. My research is centered around deciphering the hints that the distribution of stars in galaxies provides about the dispersion of dark matter, and investigating how remote galaxies amalgamate to form the universe’s largest structures, known as galaxy clusters. By integrating these two focus areas, I aim to concurrently comprehend the influence of dark matter on scales ranging from the “small” hundreds of light-years to the colossal scales exceeding 1 million light-years. The task of demystifying the nature of dark matter requires a collaborative effort encompassing observational and computational astrophysics, as well as experimental and theoretical physics. As an observational astrophysicist, my role involves analyzing and quantitatively characterizing the impact of dark matter on ordinary matter, thereby aiding the advancement of pioneering experiments designed to uncover the nature of one of the most profound enigmas of the twentieth and twenty-first centuries.