Stellar Effective Surface Temperatures

Use the table to determine the surface temperature of a star whose spectral class and luminosity class you know. Find the row for the spectral class and the column for the luminosity class. The number is the star’s effective surface temperature in kelvin (K).

Spectral class	LC V: main sequence	LC III: giants	LC I: supergiants
O3	52500	50000	47300
O4	48000	45500	44100
O5	44500	42500	40300
O6	41000	39500	39000
O7	38000	37000	35700
O8	35800	34700	34200
O9	33000	32000	32600
B0	30000	29000	26000
B1	25400	24000	20800
B2	22000	20300	18500
B3	18700	17100	16200
B5	15400	15000	13600
B6	14000	14100	13000
B7	13000	13200	12200
B8	11900	12400	11200
B9	10500	11000	10300
A0	9520	10100	9730
A1	9230	9480	9230
A2	8970	9000	9080
A3	8720	8600	8770
A5	8200	8100	8510
A7	7850	7650	8150
A8	7580	7450	7950
F0	7200	7150	7700
F2	6890	6870	7350
A5	6440	6470	6900
A8	6200	6150	6100
G0	6030	5850	5550
G2	5860	5450	5200
G5	5770	5150	4850
G8	5570	4900	4600
K0	5250	4750	4420
K1	5080	4600	4330
K2	4900	4420	4250
K3	4730	4200	4080
K4	4590	4000	3950
K5	4350	3950	3850
K7	4060	3850	3700
M0	3850	3800	3650
M1	3720	3720	3550
M2	3580	3620	3450
M3	3470	3530	3200
M4	3370	3430	2980
M5	3240	3430	2800
M6	3050	3330	2600
M7	2940
M8	2640

Data are from Kenneth R. Lang.  Astrophysical Data.  New York: Springer-Verlag, 1991, pp. 137–142. In that compilation, Lang in turn cites Schmidt-Kaler, T. H.  “Physical Parameters of the Stars,” in Landolt-Bornstein New Series, Volume 2b, astronomy and astrophysics–stars and star clusters.  Schaifers, K.; Voight, H. H., eds.  New York: Springer-Verlag, 1982.