The next biggest moon after The Big Four is way smaller; named Amalthea, it's an irregular lump about 250 km across its longest dimension.

除去四大卫星之外，最大的木卫是木卫五，叫做阿曼尔赛，它就小多了，是一个不规则团块，最长处有250千米。

It was not recognised at all as being anything interesting when it was discovered, it was just a corroded lump about the size of a large dictionary.

刚被发现的时候，根本没人对它感兴趣，认为这只是个跟一本大字典差不多大小的生锈金属块而已。