| Earth’s core | C-type | S-type | Martian |
Thermal (<0.5 eV) | 0.147 | 0.185 | 0.238 | 0.217 |
Epithermal (0.5 eV - 500 keV) | 1.268 | 0.246 | 0.285 | 1.955 |
Fast (>500 keV) | 4.580 | 0.486 | 1.419 | 1.730 |