ΔE 8.7, close: similar, with a visible difference side by side. Orange Rust is a little darker, cooler than Mars Orange.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Orange Rust is a little darker, cooler than Mars Orange.
The same difference applies the other way round: Mars Orange is a little lighter, warmer.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Mars Orange on the colour wheel See Orange Rust on the colour wheel
All matches: Mars Orange equivalents · Orange Rust equivalents