### 9. Titan’s (Saturn’s satellite) Without-Atmosphere Effective Temperature Calculation

**9. Titan’s (Saturn’s satellite) Without-Atmosphere Effective Temperature Calculation: **

**So = 1.362 W/m² (So is the Solar constant) **

**Titan’s albedo: atitan = 0,22 **

**1/R² = 1/9,04² = 1/81 = 0,01234567 **

**Titan’s sidereal rotation period is 15,9 days **

**Titan does N = 1/15,9 rotations per day (synchronous rotation) **

**Titan is a rocky planet, it has atmosphere of 95% N2 and 5% CH4, but very opaque. Titan’s atmosphere is 8 times larger with respect to square meter planet’s surface compared to Earth, so we consider Titan a gaseous planet and Titan’s surface irradiation accepting factor Φtitan = 1. **

**Titan can be considered as a liquid methane ocean planet, **

**Cp.methane = 0,4980 cal/gr*oC **

**β = 150 days*gr*oC/rotation*cal – it is the Planet Surface Solar Irradiation Absorbing-Emitting Universal Law constant**

** σ = 5,67*10⁻⁸ W/m²K⁴, a Stefan-Boltzmann constant**

** Titan-Without-Atmosphere effective temperature Te.titan is**

** Te.titan = [ Φ (1-a) So (1/R²) (β*N*cp)¹∕ ⁴ /4σ ]¹∕ ⁴**

**Τe.titan = { 1*(1-0,22)*1.362 W/m² *0.01234*[150 *(1/15,945)*0,4980]¹∕ ⁴ /4*5,67*10⁻⁸ W/m²K⁴ }¹∕ ⁴ =**

** Te.titan = 96,03 K **

**Tsat.mean.titan = 93,7 K (- 179,5 oC) **

**Titan has an atmosphere of 95% N2 nitrogen plus 5% of greenhouse gas methane CH4. Titan has a minor greenhouse effect phenomenon. This phenomenon is so insignificant that it hasn't appeared in calculations. **