Britannia Object Catalogues: Eruptive Variable Stars

the britannia observatory

Eruptive Variable Stars

TYPE
OF
VARIABLE SPECTRA DURATION OF
INCREASED
BRIGHTNESS NORMAL
ABSOLUTE
MAGNITUDE AMPLITUDE
(Magnitudes) DESCRIPTION EXAMPLE NUMBER
KNOWN IN
GALAXY*

Novae O to A
  hot subdwarfs Months to years >0 7 to 16 Rapid rise to maximum; slow decline;
  ejection of gas shell GK Per 166

Novalike variables
  or P Cygni stars Hot B stars Erratic -3 to -6 Several magnitudes Slow, erratic, and novelike variations
  in light; may be unrelated to novae;
  Gas shell ejected P Cyg 39

Supernovae ? Months to years ? 15 or more Sudden, violent flareup, followed by
  decline and ejection of gas shell CM Tau
  (Crab nebula) 7

R Coronae
  Borealis F to K
  supergiant 10 to several
  hundred days -5 1 to 9 Sudden and irregular drops in brightness.
  Low in hydrogen abundance, but high in
  carbon abundance R CrB 32

T Tauri or
  RW Aurigae B to M
  main sequence
  and subgiants Rapid and erratic 0 to +8 up to a few
  magnitudes Rapid and irregular light variation.
  Generally associated with interstellar
  material. Subtypes from G to M are
  called T Tauri variables RW Aur,
  T Tau 1109

U Geminorium or
  SS Gygni or
  "dwarf novae" A to F
  hot subdwarfs Few days to few weeks >0 2 to 6 Novalike outbursts at mean intervals
  which range from 20 to 600 days.
  Those with longer intervals
  between outbursts tend to have
  greater amplitudes. Many, if not all,
  are members of binary-star systems ss Cyg,
  U Gem 215

Flare stars M
  main sequence Few minutes >8 up to 6 Sudden flareups in light; probably
  localized flares on surface of star UV Cet 28

Z Camelopardalis
  variables A to F
  hot subdwarfs Few days >0 2 to 5 Similar to U Geminorium, except that
  variations are sometimes interrupted
  by constant light for several
  cycles. Intervals between outbursts
  normally range from 10 to 40 days Z Cam 20

*According to the 1968 edition of the Soviet General Catalogue of Variable Stars.

return to Object Guides

Questions, Comments? Please Contact ASH
Database Last Updated: September 02 2017 21:54:10.
You are visitor since 29 Apr 2002


TYPE OF VARIABLE	SPECTRA	DURATION OF INCREASED BRIGHTNESS	NORMAL ABSOLUTE MAGNITUDE	AMPLITUDE (Magnitudes)	DESCRIPTION	EXAMPLE	NUMBER KNOWN IN GALAXY*

Novae	O to A hot subdwarfs	Months to years	>0	7 to 16	Rapid rise to maximum; slow decline; ejection of gas shell	GK Per	166

Novalike variables or P Cygni stars	Hot B stars	Erratic	-3 to -6	Several magnitudes	Slow, erratic, and novelike variations in light; may be unrelated to novae; Gas shell ejected	P Cyg	39

Supernovae	?	Months to years	?	15 or more	Sudden, violent flareup, followed by decline and ejection of gas shell	CM Tau (Crab nebula)	7

R Coronae Borealis	F to K supergiant	10 to several hundred days	-5	1 to 9	Sudden and irregular drops in brightness. Low in hydrogen abundance, but high in carbon abundance	R CrB	32

T Tauri or RW Aurigae	B to M main sequence and subgiants	Rapid and erratic	0 to +8	up to a few magnitudes	Rapid and irregular light variation. Generally associated with interstellar material. Subtypes from G to M are called T Tauri variables	RW Aur, T Tau	1109

U Geminorium or SS Gygni or "dwarf novae"	A to F hot subdwarfs	Few days to few weeks	>0	2 to 6	Novalike outbursts at mean intervals which range from 20 to 600 days. Those with longer intervals between outbursts tend to have greater amplitudes. Many, if not all, are members of binary-star systems	ss Cyg, U Gem	215

Flare stars	M main sequence	Few minutes	>8	up to 6	Sudden flareups in light; probably localized flares on surface of star	UV Cet	28

Z Camelopardalis variables	A to F hot subdwarfs	Few days	>0	2 to 5	Similar to U Geminorium, except that variations are sometimes interrupted by constant light for several cycles. Intervals between outbursts normally range from 10 to 40 days	Z Cam	20

According to the 1968 edition of the Soviet General Catalogue of Variable Stars*.