Input (grade 4): Romulus, the outermost moon, would be about 0.89 Â across, slightly bigger than the closer but smaller Remus, which would be about 0.78 Â across.
Output (grade 3): Romulus, the farthest moon, would be about 0.89 Â across, a bit bigger than the closer but smaller Remus, which would be about 0.78 Â across.