Observations of naturally-occurring ultraviolet radiation provide us a wealth of knowledge about the nature and mechanisms of the terrestrial atmosphere, ionosphere, and geocorona and the local interstellar medium. The ultraviolet spectrum is so valuable because it corresponds to the energies of atomic and molecular processes such as fundamental resonance transitions, ionization, and dissociation; however, these same properties make ultraviolet technology difficult. Far and extreme ultraviolet observations from rockets and satellites produce accurate synoptic views of the earth's hydrogen and helium atmospheres and their variations. Similarly, the plasmasphere, confined by the earth's magnetic field, is mapped on a global scale by the resonance radiation of the helium ions. Near the magnetic equator, ultraviolet emissions depict the unique behavior of oxygen ions and the precipitation of alpha particles. With the discovery of extended extraterrestrial ultraviolet resonance radiation from hydrogen and helium it was realized that the local interstellar medium (LISM) flows into and interacts with the solar system. The UV radiation patterns accurately define the LISM characteristics.