What material categories could a star‑faring extraterrestrial civilization use to build the hull, the structure of a true interstellar craft?

If an extraterrestrial civilization can cross interstellar distances and actually reach Earth, then the materials they use for their ship’s hull are probably far beyond anything we classify as “spacecraft materials” today. A craft like that would need to survive: extreme cosmic radiation high‑velocity micrometeoroid impacts long‑term thermal and mechanical stress and possibly the effects of whatever propulsion method they use, especially if it involves manipulating spacetime So what *kinds* o...

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