G0IV

Garrison94 lists eta Boo (HD 121370 = HR 5235) as the G0IV anchor standard, the
hottest subgiant standard on his list.

JM53 lists eta Boo and zet Her as G0IV standards. 

MK78 uses eta Boo as its G0IV standard. 

MK73 and MorganAbt72 do not list a G0IV standard.

Keenan89 lists two G0IV standards (HD 121370 and HD 150680),
plus a G0IV-V standard (HD 160269).

Houk88 adopts eta Boo (HD 121370) as their G0IV standard, from JM53.

GrayNstars lists eta Boo as their G0IV DSO standard.


# Primary Standards (J1354+1823)
HD 121370 = HR 5235 = Eta Boo
   G0IV: MK43,Barry70,Jaschek78(JM53),Jaschek64(most),Keenan89,Gray01,
   G0: Cannon
   B-V = 0.580, revised HIP => Mv=2.40, 1.94 mag above MS.

# Weak Standard
Zet Her
   G0IV: MK43,Keenan80,Keenan89,Barry70(G0IVb,uv metals weak),Stephenson69
   G2IV: Gray01
   G1IV: MK73,Abt81(standard)
   G3IV: Houk88
   F9IV+G7V: Edwards76
   G0: Cannon
   1.5" binary
   This star was also adopted as a G3IV standard by Houk!