flare star | M | | | | 0.2 magnitudes or greater | some difficulty in distinguishing between various kinds | | d | CV | 70 percent of all stars | | | | | | red dwarf | | - 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 | UV Ceti star | Stars undergoing erratic jumps in brightness (up to a few magnitudes) on time scales of the order of minutes. During the quiescent phase the spectrum is that of an M dwarf with emissions in the CaII and Balmer lines. | V | |
pulsar | | dark halo | hypothetical | inversely proportional to the wavelength | | | | | PSR | | | | | | inversely proportional to its momentum | radio star | | | | hidden mass | An object discovered at Cambridge University in 1967 which has the mass of a star and a radius no larger than that of Earth and which emits radio pulses with a very high degree of regularity (periods range from 0.03 s for the youngest to more than 3 s for the oldest). All pulsars are characterized by the general properties of dispersion, periodicity, and short duty cycle. Pulsars are believed to be rotating, magnetic (surface magnetic fields of 1010 to 1014 gauss are estimated) neutron stars which are the end products of supernovae. Type S pulsars have a simple pulse shape: Type C, complex: Type D have drifting subpulses. | | uncertainty principle |