Spacecraft Radiator Heat Rejection Calculator
Spacecraft thermal management: Calculate required thermal radiator surface area ($A_{\text{rad}}$), Stefan-Boltzmann radiative rejection power, fin efficiency factor ($\eta_{\text{fin}}$), and equivalent deep-space sink temperature ($T_{\text{sink}}$).
Thermal Dissipation & Radiator Temperature
Payload avionics + battery heat
Nominal loop temperature (~20–35 °C)
Surface Optical Properties & Coatings
White paint / Silver Teflon: 0.85–0.90
Silver Teflon: ~0.10; White paint: ~0.20
Environment & Fin Effectiveness
Deep space: 3 K; LEO Earth-facing: 150–220 K
Heat pipe embed panel: 0.85–0.95
Honeycomb panel + embedded heat pipes: 4–6 kg/m²
Radiator Sizing Output
Required Radiator Area:
--
m² (ft²)
Specific Rejection Capacity:
--
W / m²
Estimated Radiator Mass:
--
kg (lbs)
Radiator Temp in Kelvin:
--
K
| Blackbody Ideal Flux σ·T⁴: | -- |
| Environmental Sink Flux σ·T_sink⁴: | -- |
| Effective Surface Emissivity ε·η: | -- |
| Thermal Sizing Margin (Recommended): | -- |
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