A9IV There are no A9IV standards in JM53, MK73, MorganAbt72, Cowley74, Houk88, Garcia89, GrayGarrison89, nor anchor points in Garrison94. Gray06 classify two stars as A9IV: HIP 95168 and HIP 102333 GrayGarrison89 classify 17 stars as A9IV or variant. The brightest "pure" A9IV stars were HD 211336, 197157, 2628. For Hipparcos stars within 75pc with parallax S/N > 8 (N=6): (A9IV) = 0.289 (+-0.007 sem, +-0.021 stdev) (A9IV) = 0.328 (+-0.009 sem, +-0.028 stdev) (A9IV) = 0.612 (+-0.011 sem, +-0.028 stdev) (A9IV) = 0.707 (+-0.015 sem, +-0.031 stdev) (A9IV)= 0.764 (+-0.023 sem, +-0.047 stdev) (A9IV) = 0.110 (+-0.014 sem, +-0.029 stdev) (A9IV) = 0.063 (+-0.012 sem, +-0.024 stdev) (B-V)(A9IV) = 0.272(+-0.011 sem,+-0.033 stdev) ; SIMBAD median A9IV d<75pc,V<6.5(N=9) (B-V)(A9IV) = 0.284 ; (B-V)(A9IV)=0.255 plus trend seen for other IV stars => adopt (B-V)(A9IV) = 0.27 [updated 2/3/2022] Mv(A9IV) = 1.6 ; GrayCorbally09 Mv(A9IV) = 2.27(+-0.32 sem,+-0.84 stdev) ; SIMBAD median A9IV d<75pc,V<6.5(N=9) # Non-standard stars 58 Tau = HD 27459 = HR 1356 = BD+14_682 (J0420+1505; V=5.3) A7V: Adams35 A8III: Gray01 A9V: Morgan65, Peniche81 A9IV: Cowley74 A9n: Wilson48 F0IV: GrayGarrison89 F0IV: Abt95 F0V: Eggen50 This is the only Hyad classified by Morgan65 as "A9V". Frustratingly called A8/A9/F0 and V/IV/III among expert classifiers. From revised Hipparcos parallax, I estimate Mv = 1.90 and the star is 0.24 mag above the main sequence (closest to GrayCorbally10's "IV" Mv sequence). The Hyades MS turnoff is near the mid-A's, and this star does appear to be a dwarf. B-V = 0.22. For the Hipparcos Hyades (Perryman et al. 1998), (F0V) = 0.263 (range 0.22-0.32), (A8V) = 0.26 (range 0.255-0.263), (A7V) ~ 0.19 (range 0.15-0.25). A consensus estimate might be "A9IV"? HD 181577 = HR 7340 = HIP 95168 = rho01 Sgr A9IV: Gray06,Abt95 F0III-IV: GrayGarrison89 F1III: Malaroda75 F0IV-V: Cowley69 Quoted types are A9-F1, and III through IV-V. Probably not a good candidate standard. HD 197157 = HR 7920 = eta Ind (J2044-5155) A9IV: Abt95, GrayGarrison89 A7III/IV: Houk78 A6-A9: Malaroda73 A9III-IV: Levato72 F0: Cannon Good agreement on A9. Malaroda says its a spectroscopic variable, however. HD 211336 HD 2628 HD 109238 A9IV: GarrisonGray87 A9-F2 in the literature HR 1706 = HD 33959 = 14 Aur A9IV: MorganAbt72(non-stan) kA9hA9mF2: Abt95 A9V: Abt84 F0IVp?: Abt69 Abt alone coauthored 4 different papers with 4 different classifications for this star! No modern classifications by Gray.