Energetic neutral atom Energetic neutral atom Energetic neutral atom (ENA) imaging, often described as "seeing with atoms", is a technology used to create global images of otherwise invisible phenomena in the magnetospheres of planets and throughout the heliosphere, even to its outer boundary. This constitutes the far-flung edge of the solar system. The solar wind consists of ripped-apart atoms (called plasma) flying out of the Sun. This is mostly hydrogen, that is, bare electrons and protons, with a little bit of other kinds of nuclei, mostly helium. The space between solar systems is similar, but they come from other stars in our galaxy.
Plasma stealth A plasma is a "quasineutral" (total electrical charge is close to zero) mix of ions (atoms which have been ionized, and therefore possess a net positive charge), electrons, and neutral particles (un-ionized atoms or molecules). Most plasmas are only partially ionized, in fact, the ionization degree of common plasma devices like fluorescent lamp is fairly low ( less than 1%). Almost all the matter in the universe is very low density plasma: solids, liquids and gases are uncommon away from planetary bodies. Plasmas have many technological applications, from fluorescent lighting to plasma processing for semiconductor manufacture. Plasmas can interact strongly