### 8. Calisto’s (Jupiter’s satellite) Effective Temperature Calculation

**Te.calisto**

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

Calisto’s albedo: acalisto = 0,22

Calisto has a heavy cratered surface (golf ball surface) and that makes the difference with Europa, and Europa’s albedo aeuropa = 0,63.

Calisto is an ice-crust planet (rocky) without atmosphere, but Calisto has a heavy cratered surface (golf ball surface) so Calisto’s surface irradiation accepting factor Φcalisto = 1

Calisto’s surface consists of water ice crust (by estimation), so

Cp.calisto = 1cal/gr*oC

1/R² = 1/5,2044² = 0,0369 times lesser is the solar irradiation on Jupiter than that on Earth, the same on its satellite Calisto

Calisto’s orbital period is 16,689.0184 days

Calisto’s sidereal rotation period is synchronous

N = 1/16,689 rotation /day

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

Calisto’s effective temperature complete formula Te.calisto is:

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

Τe.calisto = { 1*(1-0,22)1.362W/m² *0.0369*[150*(1/16,689)*1]¹∕ ⁴ /4*5,67*10⁻⁸ W/m²K⁴ }¹∕ ⁴ =

**Te.calisto = 131,52 K **

**Tsat.mean.calisto = 134 K ± 11**

Calisto is an ice crust planet, and we know for sure that ice is not a poor emitter, ε = 0,90

(1/0,90)¹∕ ⁴ = 1,027 So we would have:

Te.calisto = 131,52 K * 1,027 = 135,071 K.

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** The faster a planet rotates (n2>n1) the higher is the planet’s average (mean) temperature T↑mean:**

** Tmin↑→ T↑mean ← T↓max**

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