Hydrogen-alpha, typically shortened to H-alpha or Hα, is a deep-red visible spectral line of the hydrogen atom with a wavelength of 656.28 nm in air and...

line is called "Lyman-alpha" (Ly-α), while the 7 → 3 line is called "Paschen-delta" (Pa-δ). There are emission lines from hydrogen that fall outside of...

A hydrogen atom is an atom of the chemical element hydrogen. The electrically neutral hydrogen atom contains a nucleus of a single positively charged proton...

Lyman-alpha, typically denoted by Ly-α, is a spectral line of hydrogen (or, more generally, of any one-electron atom) in the Lyman series. It is emitted...

sequence of amino acids. The alpha helix has a right-handed helix conformation in which every backbone N−H group hydrogen bonds to the backbone C=O group...

relative location of carbon atoms as well as hydrogen atoms to other functional groups. The α-carbon (alpha-carbon) refers to the first carbon atom that...

sign nebula". NGC 6888 in Hydrogen and Oxygen Light. HOO Palette. Imaged by Don Christopher Deaver Crescent Nebula in H-alpha and OIII. Imaged with a 715mm...

hydrogen. It has a diameter of about 4.5′, at its distance meaning it measures 2.1 ly (0.65 pc). The net (meaning omitting the star) hydrogen alpha luminosity...

sometimes called dihydrogen, but more commonly called hydrogen gas, molecular hydrogen or simply hydrogen. It is colorless, odorless, non-toxic, and highly...

with another using the PP chain. Fusing four free protons (hydrogen nuclei) into a single alpha particle (helium nucleus) releases around 0.7% of the fused...