Still other variables may be termed Irregular, for they suffer brightness changes in abrupt and unpredictable fashion. These stars may continue at a constant brightness or, after small fluctuations for years or months, drop suddenly in brightness by six magnitudes in days or weeks, and return to maximum brightness over a period of years. The most famous irregular variable is R Coronae Borealis.

Copyright (c) 1997-99 Michael Erlewine