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Ionized hydrogen in astrophysics is generally indicated by the abbreviation HII or H II (pronounced "H two") if it is a positive ion (i.e., with no electron). A more common symbol across science is H+. The vast majority of matter in the universe is such ionized hydrogen. Nearly all the interstellar medium (ISM) is basically HII (and free electrons). Also, most of the hydrogen within stars is ionized, as is much of stellar wind.
The ISM includes dense, cool, pockets of neutral atomic hydrogen (HI regions), and inside them occur smaller regions termed HII regions, hydrogen including many such ions, but at a much higher density than typical ISM. These latter are formed by ultraviolet electromagnetic radiation (EMR) (i.e., ionizing radiation) from early stars, which heats the hydrogen to thousands of degrees. Such regions imply recent star formation given these stars don't last long.
Negative hydrogen ions (H-, with two electrons orbiting, a hydrogen anion) do also exist in space. Left alone, they can persist, but a very small disturbance, such as a nearby positive ion or a photon, can release the extra electron. 13.6 eV is sufficient energy to release the electron of a neutral hydrogen atom, i.e., ionize it. However, the extra electron of a hydrogen anion can be released with much less energy than that.