I am an astrophysicist examining the Sun. I concentrate on the Sun’s remarkable capabilities for accelerating particles. Solar flares and coronal mass ejections transform huge amounts of energy from magnetic fields into kinetic energy through processes that are not yet understood. We attempt to evaluate and explain these phenomena by examining the high-energy emission from flares, all the way from large eruptive flares down to small, prevalent, unresolved ones. My main investigative tools are ultraviolet and X-ray data. I also work on the development of new instruments for high-energy exploration of the Sun, with an emphasis on X-ray sensors. Before reaching the large spacecraft stage, developing instruments are tested on sounding rockets, balloons, and CubeSats - small satellites about the size of a shoebox. In collaboration with several other institutions, we are developing hard X-ray focusing telescopes for solar purposes via the FOXSI project, which has had three successful flights on suborbital sounding rockets from the White Sands Missile Range. We are also developing CubeSats to measure X-rays from the Sun and other astrophysical objects with high time precision. The capabilities of these and other new instruments will open a new door by which we can understand some of the most energetic phenomena in the solar system.