Astrophysics

Astrophysics is the study of the universe on all physical scales–from nuclear reactions inside stars to the expansion of the universe as a whole–generally focusing on objects and physical phenomena beyond our own solar system. Areas of study include: stars (stellar astrophysics), their birth (star formation) and their death (stellar evolution); the discovery and characterization of other solar systems (exoplanetary science); the material between the stars (interstellar medium); large ensembles of stars (star clusters) and their interactions (stellar dynamics); our Milky Way galaxy and its local group of galaxies (galactic astrophysics); other galaxies (extragalactic astrophysics), their birth (galaxy formation) and their evolution (galactic evolution); the structure of the universe as a whole (large-scale structure); and the origin and evolution of the universe itself (cosmology). Astrophysics also includes the study of fundamental physics–forces, particles, the nature of matter and energy–in the astronomical context, including particle astrophysics (e.g., solar neutrinos), gravitational wave physics, the extreme physics of compact objects (e.g., black holes), dark matter, and dark energy. Astrophysics involves experimental techniques (observational astrophysics), generally involving images or spectra from telescopes on the ground and/or space, or analysis of archival datasets (data mining); theory, which includes the application of physics first-principles to derive fundamental physical laws or relationships; modeling techniques (computational astrophysics), which generally involves use of massive computing resources to simulate complex objects and phenomena; and information science (astro-informatics), which includes development and application of algorithms for the analysis, deployment, and curation of large datasets (data-intensive astrophysics).