Astronomical spectroscopy

thumb|upright|Spectral line|Absorption lines in the [[visible spectrum of a supercluster of distant galaxies (right), as compared to absorption lines in the visible spectrum of the Sun (left). Arrows indicate redshift. Wavelength increases up towards the red and beyond (frequency decreases).]]

science of temporal, spatial, and spectral distributions of radiation

classification type of a class of objects

thumb|In the Bohr model of the hydrogen atom, the electron transition from energy level n = 3 to n = 2 results in the emission of an H-alpha photon.

spectral line associated with absorption or emission of light by atomic nuclei, atoms, or molecules

indirect method for finding extrasolar planets and brown dwarfs

astronomical spectroscopic term

spectroscopic phenomenon observed when either an eclipsing binary's secondary star or an extrasolar planet is seen to transit across the face of the primary or parent star.

astronomical object type

thumb|upright|The All-sky New Horizons Alice Lyα maps in ecliptic coordinates centered on the anti-Sun direction, and the lower map is in Galactic coordinates. The c. 90,000 stars in the M. A. Velez et al. (2024) catalog are overlaid as black dots, where the size of the dot is proportional to the logarithm of the expected Alice count rate from each star. The map in Galactic coordinates indicates the outlines of four of the important LISM clouds ("LIC", in red; "Aql" in green; "Blue", in blue; and "G", in tan). Lyman-alpha, typically denoted by Ly-α or Lyα, is a spectral line of hydrogen (

Emission spectra characteristic of burning hydrocarbon fuels

correlation between width of an emission line and absolute visual magnitude of a star

difference of intensity of the stellar continuum spectrum

process in which the kinetic energy of a collision partner is converted into the

absorption features in the spectra of astronomical objects in the Milky Way and other galaxies

oxygen dication

Notation in X-ray spectroscopy

function that gives the minimum mass of a star or planet in a spectroscopic binary system