An Emission nebula is definitely an electrical phenomenon but that is not mentioned. It has what are called H II regions but what it really has is clouds of protons. These "clouds of protons" are never called that. Word selection can be either helpful or a deliberate obfuscation.
An emission nebula is a nebula formed of ionized gases that emit light of various wavelengths. The most common source of ionization is high-energy ultraviolet photons emitted from a nearby hot star. Among the several different types of emission nebulae are H II regions.
An H II region or HII region is a region of interstellar atomic hydrogen that is ionized. It is typically a cloud of partially ionized gas in which star formation has recently taken place, with a size ranging from one to hundreds of light years, and density from a few to about a million particles per cubic cm. The Orion Nebula is now known to be an H II region.
The term H II is pronounced "H two" by astronomers. "H" is the chemical symbol for hydrogen, and "II" is the Roman numeral for 2. It is customary in astronomy to use the Roman numeral I for neutral atoms, II for singly-ionised—H II is H+ in other sciences—III for doubly-ionised, e.g. O III is O++, etc. H II, or H+, consists of free protons. An H I region is neutral atomic hydrogen, and a molecular cloud is molecular hydrogen, H2. In spoken discussion with non-astronomers there is sometimes confusion between the identical spoken forms of "H II" and "H2".
so... H2 is the compound of 2 hydrogen atoms but H II is free protons and is pronunounced in "identical spoken forms " and so "there is sometimes confusion." Really?!
They may be of any shape, because the distribution of the stars and gas inside them is irregular. The short-lived blue stars created in these regions emit copious amounts of ultraviolet light that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds. They often appear clumpy and filamentary, sometimes showing intricate shapes such as the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster of stars which have formed, such as the Pleiades.
I am just amazed by the convoluted descriptions. Ionized hydrogen is a proton Partially ionized hydrogen means there are protons among the hydrogen atoms, or perhaps some electrons. The usage is not clear. H II means free protons which is definitely not clear. The word "proton" is avoided in every usage.
A region of ionized hydrogen is a cloud of protons behaving as plasma. The "millions of particles" are mostly just protons and probably some electrons to prevent their dispersion.
When a proton captures an electron the result is the emission of either the Lyman-alpha or Balmer-alpha wave lengths; both are in ultraviolet, so when an emission nebula nebula is emitting UV its loose protons are capturing electrons.
The "these regions emit copious amounts of ultraviolet light" just makes it sound magical, so welcome to the electric universe where loose protons hook up with loose electrons. [pun intended]
"They often appear clumpy and filamentary, sometimes showing intricate shapes" but this just because plasma does that. Plasma can maintain intricate shapes but the use of "molecular clouds" implies intricate shapes are incredible compared to the familiar ill defined clouds of water vapor.
To maintain a shape of atoms or particles a lattice is required. Plasma can help with that but the word "plasma" is also avoided.
On April 30, 2020 I posted: X-ray point sources around the Eagle Nebula
That post had links to images to observe:
a) the defined edges of the Pillars of Creation,
b) the presence of sheets of electrical discharge like at the solar corona, and
c) the electrically active background to sustain this coronal discharge activity at the edges of the nebula.
The edges of the nebula must have the lattice of metallic hydrogen just like the lattice of the solar surface where the coronal discharges occur.
On May 18,2020 I posted Galactic Corona Radiation. While taking the spectrum of the M33 galactic corona the spectrum of the nearby emission nebula NGC 604 was also taken.
from Wikipedia: [NGC 604] is among the largest H II regions in the Local Group of galaxies.
Here is an image of NGC 604:
NGC 604 has an impressive structure of many plasma filaments. It does not look like what might be called a "molecular cloud."
The astronomer’s slit spectrum of NGC 604 consisted of only 4 emission lines: Balmer-alpha, Balmer-beta, and ionized oxygen's O III line. The Oxygen ions and loose protons in the slice of the nebula surface had captured electrons and radiated energy with that process.
The O III emission line can be explained as, in Wikipedia’s terms: ionized gases that emit light of various wavelengths." I suppose an electric universe where ions capture electrons to illuminate the wonderful images needs to be worded in simple terms.
"clouds of protons" sounds simple.
Writing "H III" for "free protons" is incorrect simple.
Unfortunately as often demonstrated, the word "proton" is not in the appropriate vocabulary for widespread distribution.