| R Coronae Borealis variable | F star, G star |   |   | greater than 1000 Kelvin | supergiant | determined from proper motion and radial velocity | which depends on luminosity class | 0.2 magnitudes or greater |   |   | from the point of view of Earth's orbit |   | some difficulty in distinguishing between various kinds | from the point of view of Earth | or center of gravity |   | which is diffused out from the hotter core | CV |   |   | R Corona Borealis |   |   |   | 8 magnitudes | gravitational contraction and or fusion | which takes place primarily within the core | star catalog |   |   | cataclysmic variable |   |   | weak |   |   |   | hydrogen, helium | greater than 0.08 the sun's mass | - R, S, T, U, V, W, X, Y, or Z and the genitive of the latin constellation name
 - RR, RS, RT, RU, RV, RW, RX, RY, or RZ and the genitive of the latin constellation name when the single letter designations are exhausted
 - AA...AZ, BB...BZ, etc. (omitting J), which ends with QQ...QZ and the genitive of the latin constellation namewhen the RR...RZ designations are exhausted
 - V 335, V 336, etc., when the double letter designations are exhausted
 
  | within a period of decades | explosive variable | A very luminous helium-rich, carbon-rich, hydrogen-poor eruptive variable supergiant whose light declines up to 8 magnitudes at irregular intervals. | I |