Object Classification in SIMBAD

(Last revision of the classification: 07-Nov-2013)

The Object Type in Simbad is defined as a hierarchical classification: a numeric type is made of up to four levels corresponding to classes detailed below.

A presentation of the system can be found in the paper by F. Ochsenbein and P. Dubois in 'Astronomy from Large Databases II:' ed. A. Heck & F. Murtagh, 1992, pp 405-410

Note that Simbad emphasizes the physical nature of the object rather than a peculiar emission in some region of the electromagnetic spectrum or the location in peculiar clusters or external galaxies. Therefore objects are classified as peculiar emitters (classes 01. to 07.) only if nothing more about the nature of the object is known, i.e. it cannot be decided whether the object is a star, a multiple system, a nebula or a galaxy.

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Each class has normally a standard designation, a condensed one (used in tables) and an extended explanation.


Numeric Standard name Cond. Extended Explanation
00.00.00.0: Unknown ? Object of unknown nature 00.02.00.0: Transient ev transient event 01.00.00.0: Radio Rad Radio-source 01.02.00.0: Radio(m) mR metric Radio-source 01.04.00.0: Radio(cm) cm centimetric Radio-source 01.06.00.0: Radio(mm) mm millimetric Radio-source 01.08.00.0: Radio(sub-mm) smm sub-millimetric source 01.11.00.0: HI HI HI (21cm) source 01.12.00.0: radioBurst rB radio Burst 01.14.00.0: Maser Mas Maser 02.00.00.0: IR IR Infra-Red source 02.02.00.0: IR>30um FIR Far-IR source (λ >= 30 µm) 02.04.00.0: IR<10um NIR Near-IR source (λ < 10 µm) 03.00.00.0: Red red Very red source 03.03.00.0: RedExtreme ERO Extremely Red Object 04.00.00.0: Blue blu Blue object 05.00.00.0: UV UV UV-emission source 06.00.00.0: X X X-ray source 06.02.00.0: ULX? UX? Ultra-luminous X-ray candidate 06.10.00.0: ULX ULX Ultra-luminous X-ray source 07.00.00.0: gamma gam gamma-ray source 07.03.00.0: gammaBurst gB gamma-ray Burst 08.00.00.0: Inexistent err Not an object (error, artefact, ...) 09.00.00.0: Gravitation grv Gravitational Source 09.03.00.0: LensingEv Lev (Micro)Lensing Event 09.06.00.0: Candidate_LensSystem LS? Possible gravitational lens System 09.07.00.0: Candidate_Lens Le? Possible gravitational lens 09.08.00.0: Possible_lensImage LI? Possible gravitationally lensed image 09.09.00.0: GravLens gLe Gravitational Lens 09.11.00.0: GravLensSystem gLS Gravitational Lens System (lens+images) 10.00.00.0: Candidates ..? Candidate objects 10.01.00.0: Possible_G G? Possible Galaxy 10.02.00.0: Possible_SClG SC? Possible Supercluster of Galaxies 10.03.00.0: Possible_ClG C?G Possible Cluster of Galaxies 10.04.00.0: Possible_GrG Gr? Possible Group of Galaxies 10.11.00.0: Candidate_** **? Physical Binary Candidate 10.11.01.0: Candidate_EB* EB? Eclipsing Binary Candidate 10.11.10.0: Candidate_Symb* Sy? Symbiotic Star Candidate 10.11.11.0: Candidate_CV* CV? Cataclysmic Binary Candidate 10.11.11.6: Candidate_Nova No? Nova Candidate 10.11.12.0: Candidate_XB* XB? X-ray binary Candidate 10.11.12.2: Candidate_LMXB LX? Low-Mass X-ray binary Candidate 10.11.12.3: Candidate_HMXB HX? High-Mass X-ray binary Candidate 10.12.00.0: Candidate_Pec* Pec? Possible Peculiar Star 10.12.01.0: Candidate_YSO Y*? Young Stellar Object Candidate 10.12.02.0: Candidate_pMS* pr? Pre-main sequence Star Candidate 10.12.02.3: Candidate_TTau* TT? T Tau star Candidate 10.12.03.0: Candidate_C* C*? Possible Carbon Star 10.12.04.0: Candidate_S* S*? Possible S Star 10.12.05.0: Candidate_OH OH? Possible Star with envelope of OH/IR type 10.12.06.0: Candidate_CH CH? Possible Star with envelope of CH type 10.12.07.0: Candidate_WR* WR? Possible Wolf-Rayet Star 10.12.08.0: Candidate_Be* Be? Possible Be Star 10.12.09.0: Candidate_Ae* Ae? Possible Herbig Ae/Be Star 10.12.11.0: Candidate_HB* HB? Possible Horizontal Branch Star 10.12.11.2: Candidate_RRLyr RR? Possible Star of RR Lyr type 10.12.11.3: Candidate_Cepheid Ce? Possible Cepheid 10.12.12.0: Candidate_RGB* RB? Possible Red Giant Branch star 10.12.13.0: Candidate_SG* sg? Possible Supergiant star 10.12.13.3: Candidate_RSG* s?r Possible Red supergiant star 10.12.13.4: Candidate_YSG* s?y Possible Yellow supergiant star 10.12.13.5: Candidate_BSG* s?b Possible Blue supergiant star 10.12.14.0: Candidate_AGB* AB? Possible Asymptotic Giant Branch Star 10.12.15.0: Candidate_post-AGB* pA? Post-AGB Star Candidate 10.12.16.0: Candidate_BSS BS? Candidate blue Straggler Star 10.12.18.0: Candidate_WD* WD? White Dwarf Candidate 10.12.20.0: Candidate_NS N*? Neutron Star Candidate 10.12.22.0: Candidate_BH BH? Black Hole Candidate 10.12.23.0: Candidate_SN* SN? SuperNova Candidate 10.12.24.0: Candidate_low-mass* LM? Low-mass star candidate 10.12.26.0: Candidate_brownD* BD? Brown Dwarf Candidate 12.00.00.0: multiple_object mul Composite object 12.01.00.0: Region reg Region defined in the sky 12.01.05.0: Void vid Underdense region of the Universe 12.02.00.0: SuperClG SCG Supercluster of Galaxies 12.03.00.0: ClG ClG Cluster of Galaxies 12.04.00.0: GroupG GrG Group of Galaxies 12.04.05.0: Compact_Gr_G CGG Compact Group of Galaxies 12.05.00.0: PairG PaG Pair of Galaxies 12.05.05.0: IG IG Interacting Galaxies 12.09.00.0: Cl*? C?* Possible (open) star cluster 12.10.00.0: GlCl? Gl? Possible Globular Cluster 12.11.00.0: Cl* Cl* Cluster of Stars 12.11.01.0: GlCl GlC Globular Cluster 12.11.02.0: OpCl OpC Open (galactic) Cluster 12.12.00.0: Assoc* As* Association of Stars 12.13.00.0: ** ** Double or multiple star 12.13.01.0: EB* EB* Eclipsing binary 12.13.01.1: EB*Algol Al* Eclipsing binary of Algol type (detached) 12.13.01.2: EB*betLyr bL* Eclipsing binary of beta Lyr type (semi-detached) 12.13.01.3: EB*WUMa WU* Eclipsing binary of W UMa type (contact binary) 12.13.01.8: EB*Planet EP* Star showing eclipses by its planet 12.13.02.0: SB* SB* Spectroscopic binary 12.13.05.0: EllipVar El* Ellipsoidal variable Star 12.13.10.0: Symbiotic* Sy* Symbiotic Star 12.13.11.0: CataclyV* CV* Cataclysmic Variable Star 12.13.11.2: DQHer DQ* CV DQ Her type (intermediate polar) 12.13.11.3: AMHer AM* CV of AM Her type (polar) 12.13.11.5: Nova-like NL* Nova-like Star 12.13.11.6: Nova No* Nova 12.13.11.7: DwarfNova DN* Dwarf Nova 12.13.12.0: XB XB* X-ray Binary 12.13.12.2: LMXB LXB Low Mass X-ray Binary 12.13.12.3: HMXB HXB High Mass X-ray Binary 13.00.00.0: ISM ISM Interstellar matter 13.01.00.0: PartofCloud PoC Part of Cloud 13.02.00.0: PN? PN? Possible Planetary Nebula 13.03.00.0: ComGlob CGb Cometary Globule 13.04.00.0: Bubble bub Bubble 13.06.00.0: EmObj EmO Emission Object 13.08.00.0: Cloud Cld Cloud 13.08.03.0: GalNeb GNe Galactic Nebula 13.08.04.0: BrNeb BNe Bright Nebula 13.08.06.0: DkNeb DNe Dark Cloud (nebula) 13.08.07.0: RfNeb RNe Reflection Nebula 13.08.12.0: MolCld MoC Molecular Cloud 13.08.12.3: Globule glb Globule (low-mass dark cloud) 13.08.12.6: denseCore cor Dense core 13.08.12.8: SFregion SFR Star forming region 13.08.13.0: HVCld HVC High-velocity Cloud 13.09.00.0: HII HII HII (ionized) region 13.10.00.0: PN PN Planetary Nebula 13.11.00.0: HIshell sh HI shell 13.12.00.0: SNR? SR? SuperNova Remnant Candidate 13.13.00.0: SNR SNR SuperNova Remnant 13.14.00.0: Circumstellar cir CircumStellar matter 13.14.01.0: outflow? of? Outflow candidate 13.14.15.0: Outflow out Outflow 13.14.16.0: HH HH Herbig-Haro Object 14.00.00.0: Star * Star 14.01.00.0: *inCl *iC Star in Cluster 14.02.00.0: *inNeb *iN Star in Nebula 14.03.00.0: *inAssoc *iA Star in Association 14.04.00.0: *in** *i* Star in double system 14.05.00.0: V*? V*? Star suspected of Variability 14.06.00.0: Pec* Pe* Peculiar Star 14.06.01.0: HB* HB* Horizontal Branch Star 14.06.02.0: YSO Y*O Young Stellar Object 14.06.02.4: Ae* Ae* Herbig Ae/Be star 14.06.05.0: Em* Em* Emission-line Star 14.06.05.3: Be* Be* Be Star 14.06.06.0: BlueStraggler BS* Blue Straggler Star 14.06.10.0: RGB* RG* Red Giant Branch star 14.06.12.0: AGB* AB* Asymptotic Giant Branch Star (He-burning) 14.06.12.3: C* C* Carbon Star 14.06.12.6: S* S* S Star 14.06.13.0: SG* sg* Evolved supergiant star 14.06.13.3: RedSG* s*r Red supergiant star 14.06.13.4: YellowSG* s*y Yellow supergiant star 14.06.13.5: BlueSG* s*b Blue supergiant star 14.06.15.0: post-AGB* pA* Post-AGB Star (proto-PN) 14.06.16.0: WD* WD* White Dwarf 14.06.16.1: pulsWD* ZZ* Pulsating White Dwarf 14.06.17.0: low-mass* LM* Low-mass star (M<1solMass) 14.06.18.0: brownD* BD* Brown Dwarf (M<0.08solMass) 14.06.19.0: Neutron* N* Confirmed Neutron Star 14.06.23.0: OH/IR OH* OH/IR star 14.06.24.0: CH CH* Star with envelope of CH type 14.06.25.0: pMS* pr* Pre-main sequence Star 14.06.25.3: TTau* TT* T Tau-type Star 14.06.30.0: WR* WR* Wolf-Rayet Star 14.07.00.0: PM* PM* High proper-motion Star 14.08.00.0: HV* HV* High-velocity Star 14.09.00.0: V* V* Variable Star 14.09.01.0: Irregular_V* Ir* Variable Star of irregular type 14.09.01.1: Orion_V* Or* Variable Star of Orion Type 14.09.01.2: Rapid_Irreg_V* RI* Variable Star with rapid variations 14.09.03.0: Eruptive* Er* Eruptive variable Star 14.09.03.1: Flare* Fl* Flare Star 14.09.03.2: FUOr FU* Variable Star of FU Ori type 14.09.03.4: Erupt*RCrB RC* Variable Star of R CrB type 14.09.04.0: RotV* Ro* Rotationally variable Star 14.09.04.1: RotV*alf2CVn a2* Variable Star of alpha2 CVn type 14.09.04.3: Pulsar Psr Pulsar 14.09.04.4: BYDra BY* Variable of BY Dra type 14.09.04.5: RSCVn RS* Variable of RS CVn type 14.09.05.0: PulsV* Pu* Pulsating variable Star 14.09.05.2: RRLyr RR* Variable Star of RR Lyr type 14.09.05.3: Cepheid Ce* Cepheid variable Star 14.09.05.5: PulsV*delSct dS* Variable Star of delta Sct type 14.09.05.6: PulsV*RVTau RV* Variable Star of RV Tau type 14.09.05.7: PulsV*WVir WV* Variable Star of W Vir type 14.09.05.8: PulsV*bCep bC* Variable Star of beta Cep type 14.09.05.9: deltaCep cC* Classical Cepheid (delta Cep type) 14.09.05.10: gammaDor gD* Variable Star of gamma Dor type 14.09.05.11: pulsV*SX SX* Variable Star of SX Phe type (subdwarf) 14.09.06.0: LPV* LP* Long-period variable star 14.09.06.1: Mira Mi* Variable Star of Mira Cet type 14.09.06.4: semi-regV* sr* Semi-regular pulsating Star 14.09.08.0: SN SN* SuperNova 14.14.00.0: Sub-stellar su* Sub-stellar object 14.14.02.0: Planet? Pl? Extra-solar Planet Candidate 14.14.10.0: Planet Pl exoplanet Extra-solar Confirmed Planet 15.00.00.0: Galaxy G Galaxy 15.01.00.0: PartofG PoG Part of a Galaxy 15.02.00.0: GinCl GiC Galaxy in Cluster of Galaxies 15.02.02.0: BClG BiC Brightest galaxy in a Cluster (BCG) 15.03.00.0: GinGroup GiG Galaxy in Group of Galaxies 15.04.00.0: GinPair GiP Galaxy in Pair of Galaxies 15.05.00.0: High_z_G HzG Galaxy with high redshift 15.06.00.0: AbsLineSystem ALS Absorption Line system 15.06.01.0: Ly-alpha_ALS LyA Ly alpha Absorption Line system 15.06.02.0: DLy-alpha_ALS DLA Damped Ly-alpha Absorption Line system 15.06.03.0: metal_ALS mAL metallic Absorption Line system 15.06.05.0: Ly-limit_ALS LLS Lyman limit system 15.06.08.0: Broad_ALS BAL Broad Absorption Line system 15.07.00.0: RadioG rG Radio Galaxy 15.08.00.0: HII_G H2G HII Galaxy 15.09.00.0: LSB_G LSB Low Surface Brightness Galaxy 15.10.00.0: AGN_Candidate AG? Possible Active Galaxy Nucleus 15.10.07.0: QSO_Candidate Q? Possible Quasar 15.10.11.0: Blazar_Candidate Bz? Possible Blazar 15.10.17.0: BLLac_Candidate BL? Possible BL Lac 15.11.00.0: EmG EmG Emission-line galaxy 15.12.00.0: StarburstG SBG Starburst Galaxy 15.13.00.0: BlueCompG bCG Blue compact Galaxy 15.14.00.0: LensedImage LeI Gravitationally Lensed Image 15.14.01.0: LensedG LeG Gravitationally Lensed Image of a Galaxy 15.14.07.0: LensedQ LeQ Gravitationally Lensed Image of a Quasar 15.15.00.0: AGN AGN Active Galaxy Nucleus 15.15.01.0: LINER LIN LINER-type Active Galaxy Nucleus 15.15.02.0: Seyfert SyG Seyfert Galaxy 15.15.02.1: Seyfert_1 Sy1 Seyfert 1 Galaxy 15.15.02.2: Seyfert_2 Sy2 Seyfert 2 Galaxy 15.15.03.0: Blazar Bla Blazar 15.15.03.1: BLLac BLL BL Lac - type object 15.15.03.2: OVV OVV Optically Violently Variable object 15.15.04.0: QSO QSO Quasar