It is worse than that.
Assuming similar solar system formation physics as ours, there would have been plenty of unobtanium in the remnants from the forming of their solar system.
They shouldn't have even needed to land.
It is worse than that.
Assuming similar solar system formation physics as ours, there would have been plenty of unobtanium in the remnants from the forming of their solar system.
They shouldn't have even needed to land.