David's Astronomy - Cataclysmic Variable Stars (original) (raw)

| | RotatingVariables | | VariableStars | | HomePage | | EclipsingVariables | | | ------------------------------------------------------------------------------------------------------------------ | | ------------------------------------------------------------------------------------------------- | | ----------------------------------------------------------------------------------- | | ------------------------------------------------------------------------------------------------------------- | |

Cataclysmic Variable Star Types (CV's)		Main Project Stars
	AM	AM Herculis stars (Type AM)	| **AM Her	**
	N	Novae (Type N)	| Nova Delphini (2013)	**V2491 Cyg (2008)	** V1722 Aql (2009) **	** **GK Per	**
	SN	Supernovae (Type SN)	| SN 2006x	SN 2008ax
	UG	Dwarf Novae (Type UG)
	UGSS	SS Cygni stars (Type UGSS)	| **SS Cyg	U Gem	CY Lyr	RU Peg	**
	UGSU	SU Ursae Majoris stars (Type UGSU)	| **SU UMa	FO And	**
	ER UMa subtype	**| RZ LMi	ER UMa	**
	UGWZ	WZ Sge stars (UGWZ)	**| WZ Sge	**
	UGZ	Z Camelopardalis stars (Type UGZ)	**| RX And	TT Ari	SY Cnc	CN Ori	**
	ZAND	Z Andromedae stars (Type ZAND)	**| Z And	CI Cyg	**
	Other/Mixed Types
	UX - novalike variable (UX UMa subtype)	**| UX UMa	**
	VY - novalike variable (VY Scl subtype)	| **KR Aur	**
	Interacting binary white dwarfs (Type IBWD)	| **AM CVn	**
	Other Stars (Type *)	| **FG Sge	**
	More Information	Catalog and Atlas of Cataclysmic Variables [http://archive.stsci.edu/prepds/cvcat/index.html

Cataclysmic variables (CV's)

Novae, dwarf novae and closely related objects that undergo outbursts that are typically capable of repetition. They are normally interacting binaries comprising a cool stars usually near the main sequence , which fills its Roche lobe and loses matter in the direction of a white dwarf companion, usually forming and accretion disk. Most CV's show outbursts, typically repeated, which may be due to the burning of hydrogen to helium in a thermonuclear runaway on the surface of the white dwarf (novae), or to the pulsed release, in the form of light and heat, of gravitational energy from material falling towards the white dwarf (dwarf novae).

AM Herculis stars (Type AM)

AM Her type variables; close binary systems consisting of a dK-dM type dwarf and of a compact object with strong magnetic field, characterized by variable linear and circular polarization of light. The total range of light variations may reach 4-5 mag V.

Back to Top

AM Her - Variable Star (Polar)

Back to Top

Novae (Type N)

Novae. Close binary systems with orbital periods from 0.05 to 230 days. One of the components of these systems is a hot dwarf star that suddenly, during a time interval from one to several dozen or several hundred days, increases its brightness by 7-19 mag in V, then returns gradually to its former brightness over several months, years, or decades. Small changes at minimum light may be present. Cool components may be giants, subgiants, or dwarfs of K-M type. The spectra of novae near maximum light resemble A-F absorption spectra of luminous stars at first. Then broad emission lines (bands) of hydrogen, helium, and other elements with absorption components indicating the presence of a rapidly expanding envelope appear in the spectrum. As the light decreases, the composite spectrum begins to show forbidden lines characteristic of the spectra of gas nebulae excited by hot stars. At minimum light, the spectra of novae are generally continuous or resemble the spectra of Wolf-Rayet stars. Only spectra of the most massive systems show traces of cool components. Some novae reveal pulsations of hot components with periods of approximately 100 s and amplitudes of about 0.05 mag in V after an outburst. Some novae eventually turn out to be eclipsing systems. According to the features of their light variations, novae are subdivided into fast (NA), slow (NB), very slow (NC), and recurrent (NR) categories.

NA
Fast novae displaying rapid light increases and then, having achieved maximum light, fading by 3 mag in 100 or fewer days (GK Per);

NB
Slow novae that fade after maximum light by 3 mag in >= 150 days (RR Pic). Here the presence of the well-known "dip" in the light curves of novae similar to T Aur and DQ Her is not taken into account: The rate of fading is estimated on the basis of a smooth curve, its parts before and after the "dip" being a direct continuation of one another;

NC
Novae with a very slow development and remaining at maximum light for more than a decade, then fading very slowly. Before an outburst these objects may show long-period light changes with amplitudes of 1-2 mag in V (RR Tel); cool components of these systems are probably giants or supergiants, sometimes semiregular variables, and even Mira variables. Outburst amplitudes may reach 10 mag. High excitation emission spectra resemble those of planetary nebulae, Wolf-Rayet stars, and symbiotic variables. The possibility that these objects are planetary nebulae in the process of formation is not excluded;

NL
Novalike variables, which are insufficiently studied objects resembling novae by the characteristics of their light changes or by spectral features. This type includes, in addition to variables showing novalike outbursts, objects with no bursts ever observed; the spectra of novalike variables resemble those of old novae, and small light changes resemble those typical for old novae at minimum light. However, quite often a detailed investigation makes it possible to reclassify some representatives of this highly inhomogeneous group of objects into other types;

NR
Recurrent novae, which differ from typical novae by the fact that two or more outbursts (instead of a single one) separated by 10-80 years have been observed (T CrB).

Back to Top

Nova Delphini (2013) - nova

**Nova Delphini (2013) (Delphinus)**Nova Delphini was discovered on 14th August 2013 by Japanese observer Koichi Itagaki at magnitude +6.8. Koichi had imaged the same field the day before and nothing was visible at the same location.The progenitor star was identified from archive images as being magnitude +16.9The image below was taken 25 days after discovery when nova had faded to around +7.5The Nova is the brightest object in the image.
CCD Image (cropped)5 x 5 sec exposure (average combine), 3x3 binning, C Filter2013-09-08 22:19hUT (#546057-61)12" LX200R (at f/9.7) + ST-10XME

Back to Top

V2491 Cyg - nova

V2491 Cyg (Cygnus) Nova 'V2491 Cyg' was discovered in Cygnus by Koichi Nishiyama, Kurume, Fukuoka-ken, Japan, and Fujio Kabashima, Miyaki-cho, Saga-ken, Japan, on unfiltered CCD images taken 2008-04-10.728 UT at magnitude 7.7 (IAU Circular No. 8934)(AAVSO Special Notice #103)Image below (2008-04-14.98 UT) was taken 4.25 days above discovery.Estimated magnitude +8.5 (C)
Annotated CCD Image 20s exposure, 2x2 binning, C Filter 2008-04-14 23:30hUT (#281142)
Sequence of CCD images of V2491 Cyg taken at varying dates after discovery
4.25 days (mag +8.5)	Pre-Nova (DSS image)
3x20s exposure (average combine), 2x2 binning, C Filter 2008-04-14 23:48hUT (#281164-66)	DSS imageSame field of view as image to left [ image from http://archive.stsci.edu/cgi-bin/dss_form ]
22.3 days (mag +10.8)	59.3 days (mag +14.0)
3 x 120s exposure (average combine), 2x2 binning, C Filter 2008-05-03 00:56hUT (#285129-31)	3 x 120s exposure (average combine), 2x2 binning, C Filter 2008-06-08 23:56hUT (#290054-56)
71.3 days (mag +14.4)	83.3 days (mag +14.8)
3 x 120s exposure (average combine), 2x2 binning, C Filter 2008-06-20 23:47hUT (#291042-44)	3 x 120s exposure (average combine), 2x2 binning, C Filter 2008-07-02 23:54hUT (#293040-42)
415 days (mag < +16 )	Pre-Nova (DSS image)
3 x 45s exposure (average combine), 3x23 binning, C Filter 2009-05-31 01:02hUT (#371200-02)12" LX200 R + ST-10XME	DSS imageSame field of view as image to left [ image from http://archive.stsci.edu/cgi-bin/dss_form ]
V2491 Cyg - Light Curves showing decline from discovery (+7.7) down to final measurement (+14.8)
V2491 Cyg - Reference Stars
Annotated CCD Image 15s exposure, 2x2 binning, V Filter 2008-04-14 23:51hUT (#281171)
Identification of precursor star to V2491 Cyg Nova
V2491 Cyg 59.3 days after discovery	Pre-Nova (DSS image)
3 x 120s exposure (average combine), 2x2 binning, C Filter 2008-06-08 23:56hUT (#290054-56)	DSS imageSame field of view as image to left [ image from http://archive.stsci.edu/cgi-bin/dss_form ]

Back to Top

V1722 Aql - Nova Aquilae 2009

V1722 Aql / Nova Aquilae 2009 (Aquila) Nova discovered by Koichi Nishiyama, & Fujio Kabashima (Japan) at magnitude 10.9 on 2009-12-14.40 Image (2009-12-26.77) was taken 12.4 days after discovery.V filter images taken at same show the nova with magnitude +12.32
Annotated CCD Image (cropped)3 x 15sec (average combine), 2x2 binning, C Filter2009-12-26 18:32 h UT (#408034-42)12" LX200R (at f/5.7) + ST-10XME
V1722 Aql- Detail
CCD Image (cropped)Image details as above Alternate Black/White range
V1722 Aql- Reference Stars
C Star : 000-BJS-297 / GSC 1599:3910, (V Mag 11.571) K Star : 000-BJS-296 / GSC 1599:3038, (V Mag 11.358) V filter image showing the nova with magnitude +12.32 (check star +11.42 vs expected value of +11.36)
Annotated CCD Image (cropped)5s exposure, 2x2 binning, V Filter2009-12-26 18:31 h UT (#408036)12" LX200R (at f/5.7) + ST-10XME

Back to Top

GK Per - Variable Star, Nova (1901) : (Type: NA + XP)

GK Per (Perseus) GK Per is star which had a nova eruption in 1901, and undergoes occasional minor outbursts since then. It is reported to have begun a new outburst (Sept 2008)Images collected in VR filters
GK Per - reference stars
Annotated CCD Image 3 x 30s exposure (average combine), 2x2 binning, V filter, 2008-09-28 20:44h UT (#307056-60
GK Per - earlier image (2008-09-27)
Annotated CCD Image 3 x 30s exposure (average combine), 2x2 binning, C filter, 2008-09-27 21:41h UT (#306152-58)
GK Per - variation
Mar 2010 Outburst

Back to Top

Supernovae (Type SN)

Supernovae (B Cas, CM Tau). Stars that increase, as a result of an outburst, their brightnesses by 20 mag and more, then fade slowly. The spectrum during an outburst is characterized by the presence of very broad emission bands, their widths being several times greater than those of the bright bands observed in the spectra of novae. The expansion velocities of SN envelopes are in the thousands of km/s. The structure of a star after outburst alters completely. An expanding emission nebula results and a (not always observable) pulsar remains at the position of the original star. According to the light curve shape and the spectral features, supernovae are subdivided into types I and II.

SNI
Type I supernovae. Absorption lines of Ca II, Si, etc., but no hydrogen lines are present in the spectra. The expanding envelope almost lacks hydrogen. During 20-30 days following maximum light, the brightness decreases by approximately 0.1 mag per day, then the rate of fading slows and reaches a constant value of 0.014/day;

SNII
Type II supernovae. Lines of hydrogen and other elements are apparent in their spectra. The expanding envelope consists mainly of H and He. Light curves show greater diversity than those of type I supernovae. Usually after 40-100 days since maximum light, the rate of fading is 0.1 mag per day.

Back to Top

SN 2006x - Type 1a Supernova

SN 2006x in M100 (Ursa Major) 2006x was discovered 2006/02/04 by Shoji Suzuki; M. Migliardi (CROSS)(Rochester Supernova site |Discovery Image	Discovery Image 2	Reference Image)Image below (2006-02-20.9708) was taken 16 days after discovery. Estimated magnitude of 2006x is +13.7 (C filter). This is possibly at around peak brightness, magnitude at discovery was +17 (C)
Annotated CCD Image5 x 2 min exposure (average combine), 2x2 binning, C Filter 2006-02-20 23:17h UT (#115064-68)
	M100 Reference Image, 2004Pre-SN 2006x CCD Image (200% size)5 x 1 min exposure (average combine), 2x2 binning, C Filter 2004-03-29 01:02h UT (#64207-11)
	**SN 2006x, 2006-02-2016 days after discoverySN Est. Mag +13.7 (C Filter)**CCD Image (200% size)5 x 2 min exposure (average combine), 2x2 binning, C Filter 2006-02-20 23:17h UT (#115064-68)
	**SN 2006x, 2006-04-2378 days after discoverySN Est. Mag +15.7 (C Filter)**CCD Image (200% size)5 x 2 min exposure (average combine), 2x2 binning, C Filter 2006-04-23 22:26h UT (#116082-86)

Back to Top

SN 2008ax - Type II Supernova

**SN 2008ax in NGC 4490 (Canes Venatici)**2008ax (Type II) was discovered 2008/03/03.45 by LOSS; Koichi ItagakiMagnitude at discovery +16.1 (C)(Rochester Supernova site |LOSS Discovery Image	Itagaki Discovery Image	Reference Image) Image below (2008-03-08.03) was taken 4.6 days after discovery.Estimated Magnitude +15.2 (C)
NGC 4490 before SN2008ax(Feb 2008)	NGC 4490 with SN 2008ax (Mar 2008)
Annotated CCD Image7 x 120s exposure (average combine), 2x2 binning, C Filter 2008-02-14 04:00 hUT (#263704-10	Annotated CCD Image7 x 120s exposure (average combine), 2x2 binning, C Filter 2008-03-08 00:48 hUT (#273136-42)

Back to Top

Dwarf Novae (Type DG)

Dwarf Nova, sometimes call U Geminorum stars, but is a term also for used for types UGSS and UGSU only, and not UGZ. Close binary systems consisting of a dwarf or subgiant K-M star fillings its inner Roche lobe, and a white dwarf surrounded by an accretion disk. Orbital periods range from 0.05 - 0.5 days. From time to time the brightness of the system increases rapidly by several magnitudes, and after days or weeks it returns to its original state. The pauses between two consecutive outbursts for a given star may vary over a wide range , but every star is characterised by a certain mean value of the cycle length. Longer cycles tend to be followed by outbursts of greater amplitude. Some systems are eclipsing and the primary minimum appears to be due to the eclipse of a hot spot on the accretion disk, where matter falls in a gaseous stream from the donor star.

U Gem variables may be subdivided into three types:

SS Cyg (Type UGSS)
SU UMa (Type UGSU)
Z Cam (Type UGZ)

SS Cygni stars (Type UGSS)

Dwarf Nova in which visual brightness increases by 2 - 6 mag in 1 - 2 days, and the star returns to its original brightness over several days. Cycle lengths range from 10 to several thousand days. Examples SS Cyg,U Gem.

SS Cyg (UGSS )

Measurements being made in B, V, R & I filters as part of ongoing study.

SS Cyg (Cygnus)
Annotated CCD Image20s exposure, 2x2 binning, C Filter 2006-05-24 23:48 hUT (#127066)
SS Cyg - Reference Stars
SS Cyg variation
SS Cyg variation by colour band (QC Plots)
Animated CCD Sequence (V Band) showing +3.5 mag brightening of SS Cyg
Animated CCD Image 3 frames (3 x 30s,median combine), V filter2006-06-15 (#128034-36), V mag +13.02006-06-25 (#129134-36), V Mag + 9.02006-07-17 (#130025-27), V Mag +13.2
SS Cyg - Light Variation - December 2006 Dataset comprising 15 nights of observations
SS Cyg - Light Variation - August/September 2007 Dataset comprising 11 nights of observations
**SS Cyg - Light Variation (Aug 2007-Jan 2008)**Regular photometric measurements of SS Cyg seem to indicate that Jan 2008 cataclysmic eruption is noticeably less bright than normal eruptions
SS Cyg - Magnitude and Colour Variation between 2006-05-24 and 2007-09-15
SS Cyg (Cygnus)
Approximate Colour CCD Image (LRGB)Luminance : 2 x 20s exposure (average combine, C Filter),Red : 3 x 30s exposure (average combine, R Filter),Green : 3 x 30s exposure (average combine, V Filter), Blue : 3 x 60s exposure (average combine, B Filter)2 x 2 binning 2006-05-24 23:52 hUT (#127066-76)
Plots of 2006 Data
SS Cyg variation by colour band (QC Plots)

Back to Top

U Gem - Dwarf Nova

U Gem (Gemini) U Gem is a dwarf nova which erupts every ~100 days, rising from 14th to 9th magnitude
U Gem at Mag +13.5
CCD Image 3 x 20s exposure (average combine), 2x2 binning, C filter, 2007-02-04 20:47h UT (#174176-86)
U Gem - Approximate Colour
Approximate Colour CCD Image (LRGB)Luminance: av 3 x 20s (C Filter), Red: av 3 x 20s (R Filter)Green : av 3 x 30s (V Filter), Blue : av 3 x 60s (B Filter)2007-02-04 20:47h UT (#174176-89)
U Gem - Baseline ImageU Gem : Estimated V Mag +13.65 [ using reference Star : GSC 1375:804 V Mag 11.27 from UCAC 2.0 ]
CCD Image 3 x 30s (average combine), 2x2 binning, V Filter 2007-02-04 20:47h UT (#174178-88)
U Gem variation
U Gem Eruption - Feb 2008

Back to Top

CY Lyr - Dwarf Nova (Type UGSS)

**CY Lyr (Lyra)**CY Lyr is a dwarf nova varying between +13.2 to + 17.0 mag
Annotated CCD Image 3 x 60s sec exposure (average combine), 2x2 binning, V Filter2007-10-22 23:47 h UT (#224278-80)[AAVSO Star Chart for CY Lyr ]
CY Lyr - Reference Stars Dwarf Nova CY Lyr can be easily seen as mag +13.2 star( The Mag Limit of image is ~ +15 and thus 180s exposures will be better in future to spot CY Lyr at minimum,+17 )
Annotated CCD Image (Image details as above)
Earlier Image of CY Lyr from 2006Dwarf Nova CY Lyr is too faint to see in this 3 x 2 min image. Magnitude limit is ~ +15.8/+16
Annotated CCD Image 3 x 120s sec exposure (average combine), 2x2 binning, V Filter2006-09-08 22:58 h UT (#141205-07)[AAVSO Star Chart for CY Lyr ]
CY Lyr variation

Back to Top

RU Peg - Dwarf Nova (Type UGSS)

RU Peg (Pegasus)
CCD Image 30s exposure, 2x2 binning, C Filter2006-11-16 21:52h UT (#152216)
RU Peg outburst (2002) - north down
RU Peg - Photometry Results

Back to Top

SU Ursae Majoris stars (Type UGSU)

Dwarf Nova characterised by the presence of two types of outburst: normal ones and supermaxima. Normal outbursts are similar to those of UGSS stars. Supermaxima are typically brighter than normal ones by 2 mag., more than five times longer and at least three times less frequent than normal maxima. During supermaxima the light curves show superimposed periodic oscillations (superhumps), whose period is close to the orbital one and whose visual amplitude is about 0.2 - 0.3 mag. The orbital periods are shorter than 0.1 day. Examples SU UMa.

SU UMa - Cataclysmic variable star

SU UMa (Ursa Major)
Annnotated CCD Image 3 x 60s exposure (average combine), 2x2 binning, C filter, 2007-03-12 23:59h UT (#182288-92)
SU UMa reference stars
Annotated CCD Image 120s exposure, 2x2 binning, V filter, 2007-03-12 23:57h UT (#182289)
SU UMa Photometry
Animation sequence of images showing variation in SU UMa (images from 5 separate nights between Apr 2007 & Oct 2007)
Animated CCD Images180 sec exposure, 2x2 binning, V Filter2007-04-28 (#192248), 2007-08-08 (#203184), 2007-08-22 (#206056)2007-08-25 (#207032), 2007-10-17 (#221109)

Back to Top

RZ LMi - (Type UGSU / ER UMa)

RZ LMi (Leo Minor) RZ LMi is an ER UMa type star. These stars typically spend a third of their time in superoutburst with a supercycle of 20-50 days. Outside of superoutburst they typically pack in a rapid succession of normal outbursts, showing one every ~ 4 days RZ LMi is the star with the shortest known supercycle, spending half its time in superoutburst and has time for only two normal outbursts in between.Estimated magnitude of RZ LMi in following image is +16.5 which indicates a brightness lying between outbursts)
CCD Image 3 x 60s exposure (average combine), 2x2 binning, C filter, 2007-02-04 22:37h UT (#174319-25)
Annotated CCD Image 180s exposure, 2x2 binning, C filter, 2007-03-12 22:46h UT (#182245)
RZ LMi Light Curves

Back to Top

ER UMa (Type UGSU / ER UMa)

ER UMa (Ursa Major) ER UMa is the prototype ER UMa type star. These stars typically spend a third of their time in superoutburst with a supercycle of 20-50 days. Outside of superoutburst they typically pack in a rapid succession of normal outbursts, showing one every ~ 4 days
CCD Image 60s exposure, 2x2 binning, C filter, 2007-02-04 23:31h UT (#174370)
ER UMa - Reference Stars
CCD Image 180s exposure, 2x2 binning, V filter, 2007-03-12 23:33h UT (#182273)
ER UMa Variation (2007)

Back to Top

FO And (Type UGSU)

FO And (Andromeda)
Annotated CCD Image 120s sec exposure, 2x2 binning, C Filter 2008-12-02 20:28 h UT (#330090)
FO And - reference stars
Annotated CCD ImageImage details as above

Back to Top

WZ Sge stars (UGWZ)

Dwarf Nova. Examples WZ Sge

WZ Sge (Type UGWZ)

**WZ Sge (Sagitta)**WZ Sge has been described as the King of Cataclysmics. Although outbursts are rare they are understood to be spectacular when they do occur, with rapid nova-like brightening and interestingly superhumps, eclipses and a long decay profile [ VSNet WZ Sge Page ]GCVS Catalog details :UGSU+E+ZZ (+7.0 to +15.53) Outbursts in 1978, 2001
WZ Sge - Reference Stars
Annotated CCD Image 120 sec exposure, 2x2 binning, V Filter 2008-09-22 21:20h UT (#304061)
WZ Sge - detail WZ Sge measured mag +15.2
Annotated CCD Image (200% size, cropped)3 x 120 sec exposure (average combine), 2x2 binning, V Filter2008-09-22 21:18h UT (#304059-61) [for comparison seeoutburst image of WZ Sge by G. Masi ]

Back to Top

Z Camelopardalis stars (Type UGZ)

UGZ stars show cyclic outbursts but differ from UGSS stars in that sometimes after outburst they do not return to their original brightness but remain at an intermediate magnitude for the duration of several cycles. The cycle lengths are from 10 to 40 days, an dthe visual amplitudes are from 2 to 5 mag. Examples Z Cam, TT Ari

RX And [UGZ]

RX And (Andromeda)Variable Type UGZ
Annotated CCD Image3 x 30 sec exposure (average combine), 2x2 binning, C Filter2007-10-23 00:01hUT (#224288-94)
RX And - Reference Stars
Annotated CCD Image45 sec exposure, 2x2 binning, V Filter2007-10-22 23:59hUT (#224289)
Earlier Images of RX And from 2002showing light variation (animated frames)
Animated CCD Image (from 2002-10-03 to 2002-11-24)
RX And Photometry Results
NSV 389 Photometry Results

Back to Top

TT Ari (Type UGZ)

TT Ari (Aries)
Annotated CCD Image3 x 30 sec exposure (average combine), 2x2 binning, C Filter2007-10-22 23:33hUT (#224259-65)
TT Ari with several distant galaxies(PGC catalog mags +16.0 to +17.3)
Annotated CCD Image(Image details as above)
TT Ari - Reference Stars
Annotated CD Image45 sec exposure, 2x2 binning, V Filter2007-10-22 23:31hUT (#224260)
TT Ari Photometry Results

Back to Top

SY Cnc (Type UGZ)

SY Cnc (Cancer)
Annotated CCD Image 3 x 60s exposure (average combine), 2x2 binning, C filter, 2007-03-12 21:48h UT (#182198-202)
SY Cnc - reference stars
Annotated CCD Image 120s exposure, 2x2 binning, V filter, 2007-03-12 21:47h UT (#182199)
SY Cnc Variation (2007)

Back to Top

CN Ori (Type UGZ)

CN Ori (Orion)
Annotated CCD Image 3 x 45s sec exposure (average combine), 2x2 binning, C Filter2008-11-28 02:12 h UT (#326479-85)
CN Ori - reference stars
Annotated CCD Image90s sec exposure, 2x2 binning, V Filter2008-11-28 02:13 h UT (#326483)
CN Ori Cnc Variation (2008-2009)

Back to Top

Z Andromedae stars, or symbiotic stars (Type ZAND)

Close binaries consisting of a hot star, a star of late spectral type and an extended envelope excited by the hot star's radiation. The combined brightness varies irregularly with a visual amplitude up to 4 mag. This is a very inhomogeneous class of objects. Examples Z And.

Z And (ZAND)

Z And (Andromeda)
CCD Image
Photometry V & B Bands
Further observations will be made during future sessions in order to further refine the light / colour variation.
Z And - Colour Variation

Back to Top

CI Cyg - Variable Star (Type EA/GS+ZAND)

CI Cyg (Cygnus)
Annotated CCD Image 3 x 20s exposure (average combine), 2x2 binning, C filter, 2008-09-27 22:02h UT (#306171-79)
CI Cyg - reference stars
Annotated CCD Image 20s exposure, 2x2 binning, V filter, 2008-09-27 22:01h UT (#306173)
CI Cyg - Variation

Back to Top

Other/Mixed Types

UX - novalike variable (UX UMa subtype)

UX UMa (Type EA/WD+NL)

UX UMa (Ursa Major)
Annotated CCD Image 3 x 60s exposure (average combine), 2x2 binning, C filter, 2007-03-12 23:47h UT (#182279-832)
UX UMa - reference stars
Annotated CCD Image 120s exposure, 2x2 binning, V filter, 2007-03-12 23:49h UT (#182282)
UX UMa Variation (2007)

Back to Top

VY - novalike variable (VY Scl subtype)

KR Aur (Type VY)

KR Aur (Auriga)
Annotated CCD Image 3 x 60s exposure (average combine), 2x2 binning, C filter, 2007-03-12 22:00h UT (#182206-10)
KR Aur - reference stars
Annotated CCD Image 120s exposure, 2x2 binning, V filter, 2007-03-12 22:02h UT (#182209)
KR Aur Variation (2007)

Back to Top

IBWD - interacting binary white dwarf

AM CVn (Type IBWD)

AM CVn (Canes Venatici)
Annotated CCD Image 3 x 60s exposure (average combine), 2x2 binning, C filter, 2007-03-12 22:25h UT (#182222-24)
AM CVn - reference stars
Annotated CCD Image 120s exposure, 2x2 binning, V filter, 2007-03-12 22:31h UT (#182229)
AM CVn Variation (2007)

Back to Top

FG Sge - Variable Star (Type *)

FG Sge (Sagitta)(FG Sge appeared as AAVSO's Variable Star of the Month for June 2008 (goto article)
Annotated CCD Image 3 x 60 sec exposure (average combine), 2x2 binning, C Filter2008-08-26 02:54 UT (#297312-14)
FG Sge - reference stars
Annotated CCD Image 60 sec exposure, 2x2 binning, V Filter 2008-08-26 02:46 UT (#297306)
FG Sge - variation

Back to Top