From: Effects of dust layers on thermal emission from airless bodies
Property | Symbol | Value | Units | Comment |
---|---|---|---|---|
Solar constant | S | 1366.1 | W/m^{2} | Solar irradiance at 1 AU |
Stefan-Boltzmann constant | σ | 5.67 × 10^{−8} | W/m^{2}/K^{4} | |
Pole orientation | RA | 96.40101 | [°] | Right ascension J2000 |
DEC | − 66.39948 | [°] | Declination J2000 | |
Rotation period | P | 7.632622 | [h] | |
Obliquity | I | 171.6428 | [°] | |
Orbital period | T | 473.9 | [d] | |
Absolute time | Oct 03, 2018 | |||
Season parameter^{(1)} | L _{ p} | 153.5913 | [°] | Retrograde spin! |
Orbit parameters | e | 0.19034 | [] | Subsolar latitude − 5.277° |
Perihelion distance | q | 0.96315 | [AU] | |
Heliocentric distance | r _{ h} | 1.2447 | [AU] | Distance to Sun on Oct 3, 2018 |
Geographical latitude | ϕ | − 34.60 | [°] | MASCOT observation site |
Specific heat capacity | c _{ P} | 700 | [J kg^{−1} K^{−1}] | K ((Biele and Grott 2018), average temperature 215 K) |
Emissivity | ε | 0.90 | [] | Hemispherical NIR emissivity |
Bond albedo | A | 0.0178 | [] | |
Grain density | ρ _{ g} | 2100 | [kg m^{−3}] | |
Bedrock density | ρ _{ b} | 2000 | [kg m^{−3}] | Low porosity < 5% |
Regolith/porous rocks bulk density | ρ _{reg} | 1480 | [kg m^{−3}] | Corresponding porosity is ~ 30% |
Dust bulk density | ρ _{dust} | 366 | [kg m^{−3}] | Corresponding porosity is 83% |
Bedrock heat conductivity | k _{ b} | 1.0 | [W K^{−1} m^{−1}] | Resulting Γ = 1183 J m^{−2} K^{−1} s^{−1/2} |
Regolith heat conductivity | k _{reg} | 0.0866 | [W K^{−1} m^{−1}] | Resulting Γ = 299.5 J m^{−2} K^{−1} s^{−1/2} |
Dust heat conductivity | k _{dust} | 0.0025 | [W K^{−1} m^{−1}] | Resulting Γ = 25.31 J m^{−2} K^{−1} s^{−1/2} |