The Object Type in Simbad is defined as a hierarchical classification, which 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 (Radio, IR, Red, Blue, UV, X or gamma) 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.
Each class has normally a standard designation, a condensed one (used in tables) and an extended explanation.
The "hierarchy" column gives the list of types used behind selection criteria queries/TAP/Aladin.
- This object type is found in the literature but does not exist, or not anymore, in Simbad. However the column comments gives keys to the users to select them in the database.
- *, Ma*, bC*, sg*, s*r, s*y, s*b, WR*, N*, Psr, Y*O, Or*, TT*, Ae*, out, HH, MS*, Be*, BS*, SX*, gD*, dS*, Ev*, RG*, HS*, HB*, RR*, WV*, Ce*, cC*, C*, S*, AB*, Mi*, OH*, pA*, RV*, PN, WD*, Pe*, a2*, RC*, **, El*, EB*, SB*, BY*, RS*, Sy*, XB*, LXB, HXB, CV*, No*, SN*, LM*, BD*, V*, Ir*, Er*, Ro*, Pu*, LP*, Em*, PM*, HV*
- V*, bC*, Or*, SX*, gD*, dS*, RR*, WV*, Ce*, cC*, LP*, Mi*, RV*, a2*, RC*, El*, EB*, BY*, RS*, CV*, No*, Ir*, Er*, Ro*, Pu*
- Cl*, GlC, OpC, As*, St*, MGr
- ISM, SFR, HII, Cld, GNe, RNe, MoC, DNe, glb, CGb, HVC, cor, bub, SNR, sh, flt
- G, LSB, bCG, SBG, H2G, EmG, AGN, SyG, Sy1, Sy2, rG, LIN, QSO, Bla, BLL, GiP, GiG, GiC, BiC
- IG, PaG, GrG, CGG, ClG, SCG, vid