star naming system in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name

star atlas produced by Johann Bayer

part of astronomy concerned with mapping of stars

Betelgeuse is a red supergiant star in the equatorial constellation of Orion. It is usually the tenth-brightest star in the night sky and, after Rigel, the second brightest in its constellation. It is a distinctly reddish, semiregular variable star whose…

Red supergiants (RSGs) are stars with a supergiant luminosity class (Yerkes class I) and a stellar classification K or M.[1] They are the largest stars in the universe in terms of volume, although they are not the most massive or luminous. Betelgeuse and…

scatter plot of stars showing the relationship between the stars' absolute magnitudes (luminosities or brightness) versus their effective temperatures (stellar classifications or colour)

logarithmic measure of the luminosity of a celestial object

The UBV photometric system (from Ultraviolet, Blue, Visual), also called the Johnson system (or Johnson-Morgan system), is a photometric system usually employed for classifying stars according to their colors.
It was the first standardized photometric system.…

The electromagnetic spectrum is the full range of electromagnetic radiation, organized by frequency or wavelength. The spectrum is divided into separate bands, with different names for the electromagnetic waves within each band. From low to high frequency…

form of electromagnetic radiation

spatial period of the wave; the distance over which the wave's shape repeats; the inverse of the spatial frequency

eleventh letter of the Greek alphabet

formal system in mathematical logic

increase in the expansion rate of the universe, attributed to dark energy

relative increase in wavelength of electromagnetic radiation in the emission spectrum of astronomical objects

form of energy emitted and absorbed by particles which are charged which shows wave-like behavior as it travels through space

A gamma ray, also known as gamma radiation (symbol γ), is a penetrating form of electromagnetic radiation arising from high-energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. Lower energy gamma radiation…