- Ion (Wikipedia)
An ion (/ˈaɪ.ɒn, -ən/) is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention. The net charge of an ion is not zero because its total number of electrons is unequal to its total number of protons.
- Rigil Kentaurus (stars.astro.illinois.edu)
RIGIL KENTAURUS (Alpha Centauri) with PROXIMA CENTAURI (Alpha Cen C). Among the most famed stars of the entire sky, surely rival in renown to Sirius and Polaris even though not visible to much of the world’s population, is the “foot of the Centaur,” Rigil Kentaurus, “Rigil Kent,” the first star of Centaurus, probably much better known as Alpha Centauri or just Alpha Cen.
- Alpha Centauri (Wikipedia)
Alpha Centauri (α Centauri, Alpha Cen, or α Cen) is a triple star system in the southern constellation of Centaurus. It consists of three stars: Rigil Kentaurus (Alpha Centauri A), Toliman (B) and Proxima Centauri (C). Proxima Centauri is the closest star to the Sun at 4.2465 light-years (1.3020 pc).