Fermilab is America's particle physics and accelerator laboratory located near Batavia, IL. One of the great unsolved mysteries of the cosmos is the existence of dark matter. If so, what is it made of? With the DarkNESS CubeSat mission, FermiLab will attempt to answer those questions by searching for clues in high energy events taking place in the center of our Milky Way galaxy. By looking there for a tell-tale signal from the decay of sterile neutrinos, DarkNESS may answer these and other questions about dark matter in the near future. Darkness has completed a Preliminary Design Review and is targeted for launch in 2024.