两个结构特殊的比较句

陈大鱼

1. Although Napoleon’s army entered Russia with far more supplies than for any previous campaign, it had provisions for only twenty-four days.

2. Once positioned in space, the Hubble Space Telescope will capture light from source twenty times fainter than those that can be detected by ground-based instruments.

主要想问的是，这两个句子都是不是介宾比较？     若是的话，为什么than后面的结构完全对不上呢？

PS：还是说第二句子实际上比较的是source这名词而已。。。