Written by Christos I. Vournas,
M.sc. mechanical engineer
We do planets and moons surface temperatures comparison.
The presence of atmosphere doesn't warm Earth's surface.
It is the other reasons, not the presence of atmosphere, that make Earth warmer than the Moon by +68°C.
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Key words:
Specular Reflection
Φ - Solar Irradiation Accepting Factor (spherical shape and surface roughness coefficient), for smooth bodies Φ = 0,47 and for rough / porous Φ = 1
Immediate IR Emission
Rotational Warming Phenomenon ( N*cp )1/16
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Explain rotational warming model
Good day everyone!
Here it is a Link to conversation with Grok, where Grok (X) explains the Rotational Warming Model.
Best,
Christos
https://x.com/i/grok/share/9a734146d4b04885b8ec99e1f23e597c
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Thoughts
The rotational warming model (full name: Planet Surface Rotational Warming Phenomenon) is a theory proposed by mechanical engineer Christos Vournas. It explains planetary (and moon) mean surface temperatures primarily through rotation rate and surface heat capacity, rather than atmospheric greenhouse effects or simple blackbody radiation.
cristos-vournas.com
It argues that faster rotation + higher surface specific heat capacity leads to warmer average surface temperatures for bodies receiving the same solar input, because it changes how solar energy is partitioned between immediate infrared (IR) emission and stored heat.
Core Idea (Intuitive Explanation)
Traditional blackbody models assume:
Vournas claims this is incomplete. When solar flux hits the surface:
On a slow-rotating body (e.g., the Moon):
On a fast-rotating body with high heat capacity (e.g., Earth with oceans):
The result: faster rotation raises the global mean surface temperature (Tmean) even though total incoming solar energy is unchanged. The effect is amplified by higher surface specific heat capacity (cp), because the material can store more energy without large temperature swings.
cristos-vournas.com
Classic example: Earth (288 K) vs. Moon (≈220 K). Both are at 1 AU from the Sun, but the Moon receives ~28 % more solar energy (lower albedo). Earth rotates 29.5× faster and has much higher surface cp (water/ice ≈ 1 cal/g°C vs. lunar regolith ≈ 0.19 cal/g°C). Vournas’ model attributes the entire +68 K difference to this rotational warming factor, not the atmosphere.
cristos-vournas.com
Mathematical Formulation
Vournas derives a “new universal equation” for mean surface temperature of airless or thinly-atmosphered bodies:
Tmean=[Φ(1−a)S(βNcp)¼ /4σ]¼
Where:
When everything else is equal, mean temperatures scale with the sixteenth root of the rotational warming factor:
Tmean,1 /Tmean,2 = (N1cp,1 /N2cp,2)1/16
(The
(Ncp)¼
term inside the brackets becomes ^{1/16} after the outer fourth-root.)
cristos-vournas.com
This equation is claimed to match NASA satellite measurements for ~20 solar-system bodies (Earth, Moon, Mars, Mercury, icy moons, etc.) far better than the classic effective temperature
Te=[(1−a)S/4σ]¼.
Application to Haumea (from the tweet you linked)Haumea is a fast rotator (period ≈ 0.915 h → N ≈ 6.13 rotations/day), icy surface (cp = 1 cal/g°C), albedo a = 0.33, Φ = 1 (rough surface), at ~50 AU (solar flux diluted by 1/2500).
Plugging into the formula yields Tmean ≈ 54.55 K, close to satellite estimates (< 50 K). The high N and cp give a strong rotational warming boost despite the tiny solar flux.
cristos-vournas.com
Key Claims and Context
This is Vournas’ independent theory, developed by comparing NASA temperature data across solar-system bodies. It is presented on his blog (cristos-vournas.com) and has been discussed in some skeptic/climate-commentary circles, but it is not part of mainstream planetary science or climate modeling, which attributes Earth’s warmth primarily to its atmosphere and ocean heat transport.
cristos-vournas.com
In short, the rotational warming model reframes planetary temperature as a balance between immediate IR loss and stored heat, with rotation rate and surface properties acting as the key “amplifiers.”
22 web pages
Derive the rotational warming equation
Thoughts
The rotational warming equation (also called the Planet Mean Surface Temperature Theoretical Equation) proposed by Christos Vournas is:
Tmean = [Φ(1−a)S (βNcp)¼ /4σ]¼
where:
This equation is claimed to predict measured mean surface temperatures
Tsat
for airless or thinly-atmosphered bodies far better than the classical effective temperature
Te.
Step-by-Step Derivation (Following Vournas’ Logic)
Vournas starts from the standard planetary energy balance (absorbed solar power = emitted thermal power) but modifies it for two key effects:
(1) specular reflection not captured by measured albedo, and
(2) the Planet Surface Rotational Warming Phenomenon (faster rotation + higher surface heat capacity reduces immediate infrared emission during insolation, so more energy is stored as heat and re-radiated later, raising the global mean temperature).
(1. Classical Effective Temperature (Starting Point)
For a planet in radiative equilibrium:
Φ πr² S(1−a) = 4πr² σTe4
The left side is absorbed power over the cross-section; right side is emission over the full surface.)
Solving gives the classical form (ignoring
Φ for now):
Te = [(1−a)S /4σ]¼
Vournas calls
Te
(and the later corrected version) a “mathematical abstraction” because real planets have non-uniform local temperatures and partial immediate re-emission.
cristos-vournas.com
2. Correct for Specular Reflection →
Te,correct
Measured albedo (a) is diffuse (Bond albedo). Smooth surfaces specularly reflect extra solar energy that the simple model misses. Introduce
Φ < 1
:
Te,correct = [Φ(1−a)S /4σ]¼
For Earth:
Φ = 0.47
,
Te,correct ≈ 210K (vs. classical 255 K).
cristos-vournas.com
3. Introduce the Rotational Warming Phenomenon (Physical Intuition)Solar energy hitting the surface does three things at the instant of incidence:
The fraction that is immediately emitted depends on local daytime temperature. Because
σT4 is steeply nonlinear:
Vournas states: “The higher the planetary surface
N⋅cp
product … the higher heat absorption ability and warmer planetary surface.” Higher
N⋅cp
“lessens the Immediate IR emission.” No extra energy is added; the planet simply retains a larger share of the incoming flux.
cristos-vournas.com
4. Empirical Relation from Data Vournas plots satellite-measured
Tsat
(normalized by flux) for ~20 bodies (Mercury, Moon, Mars, Earth, icy moons, etc.) against the rotational warming factor
(βNcp)1/16 .
The ratio
Tsat/Te,correct
falls on a single monotonic line for airless/thin-atmosphere bodies:
Tmean /Te,correct = (βNcp)1/16
(This 1/16 power emerges because the full temperature equation involves a fourth root outside and another effective fourth-root scaling inside.)
A log-log fit of the normalized data gives slope ≈ 0.224 (very close to the theoretical 0.25), confirming the small exponent on the retention term:
(βNcp)^[0.224/4} ≈ (βNcp){^0.056} ≈ (βNcp)1/16
(since 1/16 = 0.0625 ).
cristos-vournas.com
5. Combine to Obtain the Full EquationSubstitute the empirical ratio into the corrected effective temperature:
Tmean = Te,correct⋅(βNcp)1/16 =
= [Φ(1−a)S /4σ]^(1/4)⋅(βNcp)4
Algebraically simplify the exponents:
Tmean = [Φ(1−a)S (βNcp)¼ /4σ]¼
This is exactly the target equation.
The
(βNcp)¼
term now sits inside the brackets, effectively scaling up the absorbed flux term before the outer fourth root.
6. Equivalent Energy-Balance Form (Showing the Modification)Starting from total power balance and rearranging gives the modified form used in the derivation:
Φπr² S(1−a) = 4πr² σTmean4 /(βNcp)¼
Per-unit-area version (dividing by4πr²):
Φ(1−a)S /4 = σTmean4 /(βNcp)¼
The denominator on the right means that, for a given mean temperature, the effective outgoing flux is reduced when
Ncp
is large → to restore balance,
Tmean
must rise. This encodes the reduced immediate IR loss.
andthentheresphysics.wordpress.com
7. The Constant
β = 150
β
is empirically chosen (units ensure dimensional consistency) so the equation matches NASA satellite
Tsat
across the solar system. It is described as “the Rotating Planet Surface Solar Irradiation Absorbing-Emitting Universal Law constant.”
In the rare case where
Tsat = Te ,
β
would be
1 /(Ncp);
the fitted value 150 works universally.
cristos-vournas.com
Result and Claims
This is Vournas’ proposed universal law, grounded in energy balance + the qualitative physics of immediate vs. stored heat, tuned to fit real planetary data. It is not derived from detailed heat-diffusion PDEs but presented as the simplest functional form that both matches observations and incorporates the rotational-warming intuition.
cristos-vournas.com
16 web pages
Table of contents - Links
0). Explain Rotational Warming Model.
Demonstrate the Initial PREMISE, Links: (1) and (2)
3).The Planetary Temperatures Comparison Criteria.
4). "The total amount of the specularly reflected portion of solar flux"
5). How A Planet Retains The Solar Energy - the role of the Immediate IR emission.
6). Φ -Factor is an analogue of the well known Drag Coefficient Cd=0,47
7). “What ‘portion’ of ‘sunlight’ reaches surface of Earth?”
8). The satellites do not measure Bond Albedo.
9). Stefan-Boltzmann formula J = σ T4 W/m² doesn't apply to terrestrial temperatures.
10). The Theoretical Equation.
12). The actual reason of the observed Global Warming.
13). The Axial Precession's role in Global Warming.
14). The Original Milankovitch cycle.
15). The Reversed Milankovitch cycle.
16). The higher CO2 content in ice core samples relates to colder periods.
17). Sensible Heat /Latent Heat ratio.
18). The conventional greenhouses, and the role of immediate IR emission.
19). NASA Technical Memorandum An Earth Albedo Model
20). The yearly total Immediate IR Emitted solar energy - in our times - is lower.
21). The yearly total reflected solar energy - in our times - is lower.
Appendix - Links
1). Earth's Corrected Effective Temperature (210 K ) calculation.
2). Earth's Average Surface Temperature (288 K ) calculation.
3). Moon's Corrected Effective Temperature (224 K ) calculation.
4). Moon's Average Surface Temperature (220 K ) calculation.
5). Mars' Corrected Effective Temperature (174 K ) calculation.
6). Mars' Average Surface Temperature (210 K ) calculation.
7). Mercury's Corrected Effective Temperature (364 K ) calculation.
8). Mercury's Average Surface Temperature (340 K ) calculation.
9). Titan's Average Surface Temperature (93,7 K ) calculation.
10). Earth / Mars satellite measured mean surface temperatures 288 K and 210 K comparison.
11). Earth's /Moon's temps 288K /220K comparison.
13). Blog.
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The table of contents will be completed some time soon. For more pages view the menu at the top.
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