In astrophysics, ionized gases or plasmas are ubiquitous. In the big bang theory, the entire universe was a plasma prior to recombination. Afterwards, much of the universe reionized after the first quasars formed and emitted radiation which reionized most of the universe, which largely remains in plasma form. These are called astrophysical plasmas. Very little baryonic matter is thought to be in atoms. In particular, the intergalactic medium, the interstellar medium, the interplanetary medium and solar winds are all diffuse plasmas, and stars are made of dense plasma. Spiral Galaxy ESO 269-57 Astrophysics is the branch of astronomy that deals with the physics of the universe, including the physical properties (luminosity, density, temperature and chemical composition) of astronomical objects such as stars, galaxies, and the interstellar medium, as well as their interactions. ... An ion is an elementary particle or system of elementary particles with a net electric charge. ... The word plasma has a Greek root which means to be formed or molded (the word plastic shares this root). ... According to the Big Bang theory, the universe originated in an extremely dense and hot state (bottom). ... Reionization is a process that occurs after the epoch of galaxy formation begins, and is the second of two major phase changes of hydrogen gas in the universe. ... This view, taken with infrared light, is a false-color image of a quasar-starburst tandem with the most luminous starburst ever seen in such a combination. ... In particle physics, the baryons are a family of subatomic particles including the proton and the neutron (collectively called Greek barys, meaning heavy, as they are heavier than the other main groups of particles. ... Intergalactic space is the physical space between galaxies. ... In astronomy, the interstellar medium (or ISM) is the matter and energy content that exists between the stars (or their immediate circumstellar environment) within a galaxy. ... The interplanetary medium is the material which fills the solar system and through which all the larger solar system bodies such as planets, asteroids and comets move. ... A solar wind is a stream of charged particles (i. ... The Pleiades star cluster A star is any massive gaseous body in outer space, just like the Sun. ...

Astrophysical plasmas are generally hot. Electrons in the plasmas are continually emitting X-rays through a process called bremsstrahlung, when electrons nearly collide with atomic nuclei. Thus, they main way of studying plasmas is through X-ray observations, performed in the upper atmosphere or space, such as by the Chandra X-ray Observatory satellite. Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... Properties The electron is a subatomic particle. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... Bremsstrahlung, German for braking radiation, is electromagnetic radiation produced by the acceleration of a charged particle, such as an electron, when deflected by another charged particle, such as an atomic nucleus. ... X-ray astronomy is an observational branch of astronomy, which deals with the study of X-ray emission from celestial objects. ... Chandra X-ray Observatory is a satellite launched on STS-93 by NASA on July 23, 1999. ...

Both plasma physicists and astrophysicists are interested in active galactic nuclei, because they are the astrophysical plasmas most directly related to the plasmas studied in the laboratory, and those studied in fusion power experiments. They exhibit an array of complex magnetohydrodynamic behaviors, such as turbulence and instabilities. Although these phenomena can occur on scales as large as the galactic core, most physicists believe that most phenomena on the largest scales do not involve plasma effects. A Plasma lamp In physics and chemistry, a plasma is an ionized gas, and is usually considered to be a distinct phase of matter. ... An active galaxy is a galaxy where a significant fraction of the energy output is not emitted by the normal components of a galaxy: stars, dust and interstellar gas. ... The Sun is a natural fusion reactor. ... MHD Simulation of Solar Wind Magnetohydrodynamics (MHD) (magnetofluiddynamics or hydromagnetics), is the academic discipline which studies the dynamics of electrically conducting fluids. ... Turbulent flow around an obstacle; the flow further away is laminar Laminar and turbulent water flow over the hull of a submarine Turbulence in the tip vortex from an airplane wing In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by low momentum diffusion, high momentum convection... Instability in systems is generally characterized by some of the outputs or internal states growing without bounds. ...

The study of astrophysical plasmas is part of the mainstream of academic astrophysics. As such, it is distinct from plasma cosmology, whose proponents believe that plasmas are responsible for long-range interactions in the universe. Plasma cosmology is a non-standard cosmological model which attempts to explain the large scale structure of the universe using electromagnetic interactions in astrophysical plasmas. ...

• "US / Russia Collaboration in Plasma Astrophysics"