Corrected Effective Temperatures of the Planets and the Planets' Mean Surface Temperature Equation: Tmean = [ Φ (1-a) S (β*N*cp)¹∕ ⁴ /4σ ]¹∕ ⁴

Plus the introduction to the Reversed Milankovitch Cycle. Click above on the box for more

Mercury imaged in enhanced color by MESSENGER in 2008

Mars pictured in natural color in 2007

4. Mercury’s Mean Surface Temperature calculation

Tmean.mercury

Surface temp..Tmin..Tmean..Tmax

Kelvin...........100.K...340.K...700.K

N = 1/175,938 rotations/per day, planet Mercury solar day is 175,938 earth days.

Mercury average distance from the sun is R=0,387AU. The solar irradiation on Mercury is (1/R)² = (1AU/0,387AU)²= 2,584²= 6,6769 times stronger than that on Earth.

Mercury’s albedo is: amercury = 0,068

Mercury is a rocky planet, Mercury’s surface irradiation accepting factor: Φmercury = 0,47

Cp.mercury = 0,20cal/gr oC, Mercury’s surface is considered as rock basalt

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

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

So = 1.362 W/m² the Solar constant

Mercury’s Mean Surface Temperature Equation is:

 

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

Tmean.mercury = { 0,47 (1-0,068) 1.361 W/m²*6,6769*[150* (1/175,938)*0,20]¹∕ ⁴ /4*5,67*10⁻⁸ W/m²K⁴ }¹∕ ⁴ = (11.271.047.334,17)¹∕ ⁴ = 325,83 K

Tmean.mercury = 325,83 K

The calculated Mercury’s Surface Mean Temperature Tmean.mercury = 325,83 K is only 4,35% lower than the measured by satellites

Tsat.mean.mercury = 340 K !


The Tmean.mercury = 325,83 K is calculated for Mercury's Semi-major axis which is 0,387 AU.

But half of the time, Mercury comes closer to the sun at its Perihelion of 0,307 AU.

The fact Mercury's orbit has high eccentricity e = 0,205 partly explains the difference between the calculated Tmean.mercury = 325,83 K and the measured Tsat = 340 K .

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http://www.cristos-vournas.com

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

Tmin→ T↑mean ← Tmax

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