Planetary Scientist’s Companion; Lodders and Fegley; Oxford Uni. Press (1998)

Variables at 100 km	Temperature (K)	Density kg/m^3	Number Density	g (m/s^2)
Venus	175.4 K	7.9 x 10^-5	1.1e15	9.5
Earth	195	5.6 x 10^-7	1.2e 13 (N2) 1.05e13(O2)	9.8
Mars	139	1.59 x 10^-9	2.2e10	3.7

Molecular Characteristics

	cross section in Mb (10^-18 cm^2) (for wavelengths in the	Recomb Rates (cm^3 s^-1)	MW
N2	0.720 (50-100) 2.26 (100-150) 4.96 (150-200) 8.4(200-250)	N2+ (2.2x10^-7)   N+ (3.6 x 10–12)	28
O2	1.316(50-100)  3.806 (100-150)  7.51 (150-200) 10.9 (200-250)	O2+ (2.4 x 10^-7)   O+(3.7 x 10^-12)	32
CO2	1.55 (50-100)  4.6(100-150)  9.09 (150-200)  14.36(200-250)	CO2+ (4.2x 10^-7)    CO+(2.75 x 10^-7)	44

Cross sections and recombination rates from Schunk and Nagy; Ionospheres, 2nd Edition; Cambridge Press (2009) F_v - solar photon flux [photon/cm^2] get from Paul's Withers paper --- at 1AU, 5 x10^10 cm^-2 per sec from 10nm -100 nm  Solar Min: EUV  Flux = 5.0e+10; Solar Max: EUV  Flux = 1.0e+11; For the Earth's Upper Atmosphere: Earth Exospheric Temp = 700 K Earth Exospheric Temp = 1400K