2007-07-19 (Protégé 3.3.1 build 430) radio#metric#m Radio Metric Cataclysmic Variable CV* cataclysmic#variable#star Binaries:cataclysmic CataclyV* Variable stars showing outbursts caused by thermonuclear burst processes in their surface layers (novae) or deep in their interiors (supernovae). We use the term "novalike" for variables that show novalike outbursts caused by rapid energy release in the surrounding space (UG-type stars) and also for objects not displaying outbursts but resembling explosive variables at minimum light by their spectral (or other) characteristics. The majority of explosive and novalike variables are close binary systems, their components having strong mutual influence on the evolution of each star. It is often observed that the hot dwarf component of the system is surrounded by an accretion disk formed by matter lost by the other, cooler, and more extended component. YSO Y*O yso#young#stellar#object YSOs YSO Recombination thermal continuum nebular#continuum Nebular Continuum Nova N GE#4320#LE#19872000 s GE#7#LE#19 7-19magV V 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, slow, very slow, and recurrent categories. Novae No* Nova nova#novae IR ir#infrared#source Infrared Source IR Synchrotron Emission emission synchrotron supernova#explosion#thermonuclear#thermo#nuclear Thermonuclear Supernova Explosion Stellar Object in Association *inAssoc *iA stellar#object#star#in#association velocity Velocity eruption#explosion#process Explosion or Eruption process Explosion or Eruption process GinGroup group#galaxy#gal#galaxies#in Galaxy in Group GiG Emission Process emission#process radio#cm#centimetric Radio Centimetric bstar#b#star B Star Star of Spectral Type B High Mass X-Ray Binary A high-mass X-ray binary (HMXB) is a binary star system where one of the components is a neutron star or a black hole. The other component is a massive star, usually a Be star or a blue supergiant. A fraction of the stellar wind of the companion star is captured by the compact star, and produces X-rays as it falls onto the compact object. In HMXB, the massive star dominates the emission of optical light. The compact object is the dominant source of X-rays. The massive stars are very luminous and therefore easily detected. One of the most famous HMXB is Cygnus X-1 which was the first stellar-mass black hole discovered. Soft-gamma rays emitters. x#ray#xray#binary#binaries#high#mass#hmxb HXB High-mass X-ray Binary HMXB Variable Star of gamma Dor type gamma#doradus#variable#star gD* gammaDor GT#43200#LT#129600 s Period of 1 day (atm transformed into -0.5 +0.5) 0.1V V GE#0.5#LE#1.5 Gamma Doradus variables are variable stars which display variations in luminosity due to non-radial pulsations of their surface. The stars are typically young, early F or late A type main sequence stars, and typical brightness fluctuations are 0.1 magnitudes with periods on the order of one day. This is a relatively new class of variable stars, having been first characterised in the second half of the 1990s, and details on the underlying physical cause of the variations remains under investigation. Gamma Doradus Variable magnetic Field magnetic#field UV uv#ultraviolet#ultra#violet#source UV UV Source HI HI hi#region#cold Cold HI Region supernova#typeii#type2#type#2#ii Supernova type II Hydrogen SNII LSB_G low#surface#brightness#lsb#gal#galaxy#galaxies Low Surface Brightness Galaxy LSB lenticular#gal#galaxy#galaxies Lenticular Galaxy Wavelength > 30 microns Far Infrared far#infrared blue Blue Low-mass X-ray Binary Low-mass X-ray binaries (LMXBs) are binary stars where one of the components is either a black hole or neutron star. The other component (donor) is usually filling its Roche lobe and therefore transfers mass to the compact star. The donor is less massive than the compact object, and can be on the main sequence, a degenerate dwarf (white dwarf), or an evolved star (red giant). Found in the Milky Way, external galaxies, and in globular clusters. A typical LMXB emits almost all of its radiation in X-rays, and typically less than one percent in visible light, so they are among the brightest objects in the X-ray sky, but relatively faint in visible light. The apparent magnitude is typically around 15 to 20. The brightest part of the system is the accretion disk around the compact object. The orbital periods of LMXBs range from ten minutes to hundreds of days. Soft-gamma rays emitters. x#ray#xray#binary#binaries#low#mass#lmxb Low Mass X-Ray Binary LMXB LXB star Star Neutron Star neutron#star Effective Temperature effective#temperature Blue Supergiant blue#super#giant#supergiant Core/Extented Flux Ratio >1 core#dominated#coredominated Core Dominated g#gstar#star G Star Star of Spectral Type G GT#10 LE#1 GT#1 Radio-loud AGN agn#radio#loud#active#galaxy#nucleus Variable Star of delta sct type DSCT PulsV*delsct GE#864#LRE#17280 s GE#0.003#LE#0.9 V 0.003-0.9V Variables of the Delta Scuti type. These are pulsating variables of spectral types A0-F5 III-V displaying light amplitudes from 0.003 to 0.9 mag in V (usually several hundredths of a magnitude) and periods from 0.01 to 0.2 days. The shapes of the light curves, periods, and amplitudes usually vary greatly. Radial as well as nonradial pulsations are observed. The variability of some members of this type appears sporadically and sometimes completely ceases, this being a consequence of strong amplitude modulation with the lower value of the amplitude not exceeding 0.001 mag in some cases. The maximum of the surface layer expansion does not lag behind the maximum light for more than 0.1 periods. Delta Sct stars are representatives of the galactic disk (flat component) and are phenomenologically close to the SX Phe variables. Sub-type: - Low amplitude group of Delta Sct variables (light amplitude <0.1 mag in V). The majority of this type's representatives are stars of luminosity class V; objects of this subtype generally are representative of the Delta Sct variables in open clusters. Delta Scuti Variable Star dS* delta#scuti#deltascuti stellar#object#star#in#double *i* A star that is part of a double star Stellar Object in Double Star *in** Stars:early-type Early-type Star Star of the early spectral types early#type#star#earlytype Radio Source Rad radio#source Radio component of the spacevelocity Proper Motion pm#proper#motion RRLyr RR Lyrae Variable RR Variables of the RR Lyrae type, which are radially-pulsating giant A-F stars having amplitudes from 0.2 to 2 mag in V. Cases of variable light-curve shapes as well as variable periods are known. If these changes are periodic, they are called the "Blazhko effect." Traditionally, RR Lyrae stars are sometimes called short-period Cepheids or cluster-type variables. The majority of these stars belong to the spherical component of the Galaxy; they are present, sometimes in large numbers, in some globular clusters, where they are known as pulsating horizontal-branch stars. Like Cepheids, maximum expansion velocities of surface layers for these stars practically coincide with maximum light. Sub-types: - RR Lyrae variables showing two simultaneously operating pulsation modes, the fundamental tone with the period P0 and the first overtone, P1 (AQ Leo). The ratio P1/P0 is approximately 0.745; - RR Lyrae variables with asymmetric light curves (steep ascending branches), periods from 0.3 to 1.2 days, and amplitudes from 0.5 to 2 mag in V; - RR Lyrae variables with nearly symmetric, sometimes sinusoidal, light curves, periods from 0.2 to 0.5 days, and amplitudes not greater than 0.8 mag in V (SX UMa). rr#lyrae#variable#star s GE#17280#LE#103680 GE#0.2#LE#2 V 0.2-2V RR* Variable Star of RR Lyr type Ultraviolet uv#ultraviolet#ultra#violet blu Blue Object blue#object Blue_objects Blue_test Blue HI HI hi#region HI Region HI (neutral) region X X-ray Source X L-type Irregular Star l#ltype#type#irregular#star Galaxy in Cluster of Galaxies GinCl Galaxy in Cluster cluster#in#galaxy#gal#galaxies GiC high#power#radio#loud#agn#active#galaxy#nucleus# High-power Radio-loud AGN fanaroff#riley#type#2 Fanaroff-Riley type 2 GT#0.5 GT#45 deg Asteroid asteroid association#star#stars Association of Stars AS* Association of Stars Associations Assoc* red#redgiant#giant Red Giant Barred Spiral Galaxy barred#spiral#galaxy#gal#galaxies BY BYDra BY* BY Draconis-type variables, which are emission-line dwarfs of dKe-dMe spectral type showing quasiperiodic light changes with periods from a fraction of a day to 120 days and amplitudes from several hundredths to 0.5 mag in V. The light variability is caused by axial rotation of a star with a variable degree of nonuniformity of the surface brightness (spots) and chromospheric activity. Some of these stars also show flares similar to those of UV Cet stars, and in those cases they also belong to the latter type and are simultaneously considered eruptive variables. by#draconis#variable#star s LE#10368000 Period less or equal than 120 days <=0.5V V LE#0.5 BY Draconis Variable Varaible Star of BY Dra type Space Velocity space#velocity Range allowing the description of the existence of a (noticeable) continuum for a given object continuum Continuum Stars showing variations of irregular (non-periodic) type. Mostly (?) of eruptive type. Variable Star of Irregular type irregular#variable#star Ir* Irregular_V* Irregular Variable Star HVCld HVC HVC (High Velocity Cloud) high#velocity#cloud#nebula High-velocity Cloud CH* ch#envelope#type#star CH* CH Envelope-type Star CH Envelope-type Star Flux flux QSO2 LumX GT#44 qso#2#quasar#qso2 kms LE#1000 QSO QSO QSO LE#45 deg kms GT#1000 qso#quasi#stellar#object#quasar#type1#type#1 quasar#qso QSO QSO Line Width line#width Starburst Process star#burst#starburst PulsV* Pulsating Variable Star Pulsating Star pulsating#variable#star Pu* Pulsating variables are stars showing periodic expansion and contraction of their surface layers. The pulsations may be radial or nonradial. A radially pulsating star remains spherical in shape, while in the case of nonradial pulsations the star's shape periodically deviates from a sphere, and even neighboring zones of its surface may have opposite pulsation phases. Depending on the period value, on the mass and evolutionary status of the star, and on the scale of pulsational phenomena, different types of pulsating variables may be distinguished. polarization Polarization emission#line#galaxy#gal#galaxies EmG EmG Emission-line galaxy Emission-line Galaxy large#separation#lobes#radio Large Separation Lobes Gamma-ray Source gam gamma#ray#source gamma pulsation#process Pulsation Process Stellar Remnant stellar#remnant High_z_G HzG Galaxy with high redshift Galaxy with High Redshift high#redshift#galaxy#gal#galaxies measure#measurement#measures#measurements Measurement Measured observational parameters/properties Stars:variable V* V* <=0.2V V LE#0.2 Eruptive variables of the RS Canum Venaticorum type. This type is ascribed to close binary systems with spectra showing Ca II H and K in emission, their components having enhanced chromospheric activity that causes quasi-periodic light variability. The period of variation is close to the orbital one, and the variability amplitude is usually as great as 0.2 mag in V (UX Ari). They are X-ray sources and rotating variables. RS CVn itself is also an eclipsing system. RS* RS Variable of RS CVn type RSCVn rs#canum#venaticorum#cv RS Canum Venaticorum Variable Star * stellar#object Stars Stellar Object Star Galaxies Galaxy G Galaxy galaxy#gal#galaxies photosphere Photosphere sub#millimetric#submillimetric#radio#source Radio(sub-mm) Sub-millimetric Radio Source smm rotation#process Rotation Process supernova#typeiib#type2b#type#2#ii#b#typeii#type2 Supernova type IIb Helium Surface Brightness surface#brightness s'applique aux objets étendus ( Gal/nebula) high#mass#star#highmass High-mass Star flux#amplitude#variation Flux Amplitude Variation AGN AGN AGN Active Galaxy Nucleus AGN#active#galaxy#nucleus#nuclei AGN dust Dust pr* pMS* Pre-main sequence star pre#main#sequence#star Pre-Main Sequence Star rotation#powered#pulsar Rotation-powered Pulsar temperature radio#millimetric#mm Radio Millimetric Spectral Type Any class in Morgan Keeman's spectral classification spectral#type FU* FU Orionis Variable Star Orion variables (eruptive) of the FU Orionis type. Characterized by gradual increases in brightness by about 6 mag in several months, followed by either almost complete constancy at maximum that is sustained for long periods of time or slow decline by 1-2 mag. Spectral types at maximum are in the range Ae(alpha) - Gpe(alpha). After an outburst, a gradual development of an emission spectrum is observed and the spectral type becomes later. These variables probably mark one of the evolutionary stages of T Tauri-type Orion variables, as evidenced by an outburst of one member, V1057 Cyg, but its decline (2.5 mag in 11 years) commenced immediately after maximum brightness was attained. All presently known FU Ori variables are coupled with reflecting cometary nebulae. Variable Star of FU Ori type fu#orionis#orion#variable#star FUOr* several months FU seyfert#seyfert1.5#1.5#galaxy SyG Seyfert 1.5 Galaxy Seyfert Type1.5-Seyfert1.5 X-Rays x#ray#xray#rays#xrays pulsating#alpha#2#alpha2#cv#cvn#canum#venaticorum Pulsating Alpha2 Canum Venaticorum s GE#345.6#LE#864 Flat-Spectrum Radio Quasar deg LE#15 LE#0.5 type 1#type1#flat#spectrum#radio#quasar#qso near#ir#infrared Wavelength < 10 microns Near Infrared gamma#rays#ray Gamma Rays Dwarf dwarf Star of Luminosity Class V Class class Radio(m) Metric Radio Source mR radio#source#metric 2 TOP TOP concept thing#top#anything pair#gal#galaxy#galaxies PairG PaG Galaxy Pair Rotationally Variable Star Variable stars with nonuniform surface brightness and/or ellipsoidal shapes, whose variability is caused by axial rotation with respect to the observer. The nonuniformity of surface brightness distributions may be caused by the presence of spots or by some thermal or chemical inhomogeneity of the atmosphere caused by a magnetic field whose axis is not coincident with the rotation axis. rotational#rotationally#variable#object#star Rotationally Variable Object Ro* RotV*