The table of Anchor Points for the MK System is taken from a paper by the author in the book "The MK Process at 50 Years," edited by Corbally, Gray and Garrison (ASP Conference Series, vol 60, 1994), pp. 3-14.
The "Anchor Points" is the subset of standard stars which have survived through the years with no change and which therefore represent the most stable points in the System. They do not form a complete grid. I am working on defining the set of "Primary Standards" which are the best current standards to use in terms of accessibility and suitability and which will represent a complete grid.
The first three columns in the table are self-explanatory. Column four is a list of classifications from the tables in the introductory booklet of the MKK Atlas (Morgan, Keenan, and Kellman, 1943). In parentheses are listed types from the Atlas which were not listed in the tables (only one star in this subset: HR 617), or which differed slightly from the types in the tables (only one star in the final list: HR 5191 and the only difference is that an "n" was added in the Atlas).
Column five is a list of classifications from Morgan's table of MK standard stars given in the UBV definition paper by Johnson and Morgan (1953). The types in the parentheses are from Michigan Publications No. X (1951).
Column six is a list of types from the 1973 Annual Reviews in Astronomy and Astrophysics article by Morgan and Keenan.
The types listed on the second page are taken from several modern lists. The second and third columns include types for stars cooler than the Sun, from various publications by Keenan and his associates. The fourth column includes types for GK stars by Morgan from an unpublished list as well as Walborn's (1973) types for O stars and Gray's (1986, 1989a,b, and 1994) types for B8-F2 stars.
Finally, all the types were checked for consistency with my own plate file. Thus, the Anchor Points represent the MK System as it was in 1943, as it was in 1953, 1973, 1978, 1989, and as it is now. The Anchor Points are the de facto standards, though they may not be the best ones or the ones we wish were standards. However, because of its long history, the MK System now has a life of its own. Instead of trying to manipulate it and distort it, we must listen to it.
MK STANDARD STARS: ANCHOR POINTS SEPTEMBER 1993 HD HR or Star MKK43 Table MK53 Table 1 MK73 Table 1,2 other Name (Atlas) (Michpub1951) (K76M78 Atlases) 47839 HR 2456 15 S Mon O7 (07) 07 (V) 214680 HR 8622 10 Lac 09 V 09 V 09 V 36512 HR 1855 upsilon Ori BO V BO V BO V 37128 HR 1903 epsilon Ori BO I BO Ia BO Ia (BO Ia) 41117 HR 2135 chi-2 Ori B2 I B2 Ia B2 Ia (B2 Ia) 206165 HR 8279 9 Cep B2 I B2 Ib (B2 Ib) 120315 HR 5191 eta UMa B3 V(n) B3 V B3 V 32630 HR 1641 eta Aur B3 V B3 V B3 V 53138 HR 2653 omicron2 CMa B3 I B3 Ia B3 Ia (B3 Iab) 58350 HR 2827 eta CMa B5 I B5 Ia B5 Ia (B5 Ia) 34085 HR 1713 beta Ori B8 Ia B8 Ia B8 Ia 103287 HR 4554 gamma UMa AO V AO V AO V 172167 HR 7001 alpha Lyr AO V AO V AO V (AO Va) 87737 HR 3975 eta Leo AO Ib AO Ib (AO Ib) 21389 HR 1040 +58 607 AO Ia AO Ia (AO Ia) 197345 HR 7924 alpha Cyg A2 Ia A2 Ia A2 Ia (A2 Ia) 216956 HR 8728 alpha PsA A3 V A3 V A3 V 89025 HR 4031 zeta Leo FO III FO III FO III (FO III) 36673 HR 1865 alpha Lep FO Ib FO Ib FO Ib (FO Ib) 113139 HR 4931 78 UMa F2 V F2 V F2 V (F2 V) 20902 HR 1017 alpha Per F5 Ib F5 Ib F5 Ib (F5 Ib) 30652 HP 1543 pi-3 Ori F6 V F6 V F6 V 194093 HR 7796 gamma Cyg F8 Ib F8 Ib (F8 Ib)(WWM) 54605 HR 2693 delta CMa F8 la F8 Ia (F8 Ia)(WWM) 109358 HR 4785 beta CVn GO V GO V GO V (PCK) 121370 HR 5235 eta Boo GO IV GO IV (GO IV)(PCK) 204867 HR 8232 beta Aqr GO Ib GO Ib GO Ib(PCK) (GO Ib) Sun Sun ASTEROIDS G2 V G2 V 20630 HR 996 kappa Cet G5 V G5 V (G5 V) 161797 HR 6623 mu Her G5 IV G5 IV G5 IV(G5 IV) note 206859 HR 8313 9 Peg G5 Ib G5 Ib G5 Ib 101501 HR 4496 61 UMa G8 V G8 V (G8 V) 188512 HR 7602 beta Aql G8 IV G8 IV G8 IV 62345 HR 2985 kappa Gem G8 III G8 III G8 IIIa 113226 HR 4932 epsilon Vir G8 III (G8III) G8 IIIab (G8 III) 48329 HR 2473 epsilon Gem G8 Ib G8 Ib G8 Ib 185144 HR 7462 sigma Dra KO V KO V KO V 62509 HR 2990 beta Gem KO III K0 III KO IIIb 197989 HR 7949 epsilon Cyg KO III K0 III KO- III 222404 HR 8974 gamma Cep K1 IV K1 IV K1 IV see notes 22049 HR 1084 epsilon Eri K2 V K2 V (K2 V) 12929 HR 617 alpha Ari (K2III) K2 III K2 IIIab 153210 HR 6299 kappa Oph K2 III K2 III K2 III 127665 HR 5429 rho Boo K3 III K3 III K3 III 31398 HR 1577 iota Aur K3 II K3 II K3 II 201091 HR 8085 61 Cyg A K5 V K5 V K5 V 164058 HR 6705 gamma Dra K5 III K5 III K5 III 6860 HR 337 beta And M0 III M0 III M0 IIIa 1013 HR 45 chi Peg M2 III M2 III M2+ III(M2 III) 39801 HR 2061 alpha Ori M2 Ib M2 Iab M1-M2 Ia-Ib 206936 HR 8316 mu Cep M2 Ia M2 Ia M2 Ia HD KY88 KY85 WWM GK STD 86 (KM89) (KP80) Walborn OB, GRAY BAF 47839 07 V((f)) 214680 09 V 36512 BO V 37128 BO Ia 41117 B2 Ia 206165 B2 Ib 120315 B3 V 32630 B3 V 53138 B3 Ia 58350 B5 Ia 34085 B8 Ia GRAYSTD/Wb 103287 A0 Van GRAYSTD 172167 A0 Va GRAYSTD 87737 A0 Ib GRAYSTD 21389 AO Ia 197345 A2 Ia 216956 A3 Va GRAYSTD 89025 F0 IIIa 36673 F0 Ib GRAYSTD 113139 F2 V 20902 30652 194093 54605 109358 GO V GO V GO V 121370 GO IV 204867 GO Ib GO Ib G2 V G2 V 20630 G5 V G5 V 161797 G5 IV G5 IV G5 IV 206859 G5 lb G5 Ib 101501 G8 V G8 V G8 V 188512 G8 IV G8 IV G8 IV 62345 G8 III G8 IIIa G8 III 113226 G8IIIab G8 IIIab 48329 G8 Ib G8 Ib 185144 KO V KO V KO V 62509 KO III 197989 KO III KO- III KO III 222404 22049 K2 V K2 V 12929 153210 K2 III K2 III 127665 K3 III 31398 201091 K5 V K5 V K5 V 164058 K5 III K5 III K5 III 6860 MO+IIIa MO+IIIa 1013 M2+ III M2+ III 39801 M1-M2Ia-Iab var M1-M2 Ia-Iab 206936 M2- Ia M2- Ia Notes: HD 161797: G5 IV in atlas illustration, but IV-V in booklet table HD 222404: K1 IV in atlas, but K1 IV CN1 in booklet table