Who is Musa from Time's Eye and what is their importance?

A tough fifty year old veteran, Musa is the commander of Soyuz. He is competent and professional, and when Discontinuity causes disruptions in his communication with the ground, he remains calm. Orbiting the silent planet he draws on his training, and shows remarkable courage. When they are almost out of their meager supplies of food and water, he orchestrates a landing. While rough, the landing is good. His bravery continues when as the first one out of the capsule, he encounters Mongolians that are part of Genghis Khan's force. He is beheaded before he can offer any explanation of their appearance.