The Sun provides a nearby case study in which to study plasma processes and high-energy astrophysical phenomena with high-resolution remote sensing combined with in-situ data and even multiviewpoint measurements — tools that are not available to study any object outside the solar system. In addition to basic physics research interests, understanding high-energy aspects of the Sun also has practical applications, since Earth-directed solar eruptive events can pose a danger to satellites, astronauts, and power grids.
New, direct-focusing techniques are now available to study high-energy aspects of solar flares and solar eruptions. The first generation of solar-dedicated hard X-ray focusing optics has recently flown on suborbital missions (rockets and balloons). And from low-Earth orbit, the NuSTAR spacecraft, a direct-focusing instrument designed to look at the faintest objects outside the solar system, has also produced detailed hard X-ray images of solar active regions.
This colloquium will cover recent advances in high-energy solar flare physics and will present new instrumentation, with emphasis on the FOXSI rocket, which produced the first focused hard X-ray image of the Sun. The prospects of these new instruments for understanding solar flares and astrophysical particle acceleration will be discussed.