Saturn is the second biggest planet in the solar system.

土星是太阳系的第二大的行星。

《柯林斯英汉双解大词典》

The picture shows six of the nine planets in the solar system.

这张图片展示太阳系9个行星中的6个行星。

《柯林斯英汉双解大词典》

Mars is the lightest planet in the solar system, which makes Mars the second smallest planet in the solar system.

火星是太阳系中最轻的行星，这使得火星成为太阳系中第二小的行星。

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An object in the solar system could be identified if it appeared to move from its place in the earlier photograph.

VOA: special.2010.07.11

It is over twenty-five kilometers high and the largest known volcano in the solar system.

VOA: special.2010.07.28

After 50 years of silence, I think the time has come to take stock and say, maybe we should mobilize all of the sciences to look for anything fishy, anything weird,any anomaly, both in our own little corner of the universe here on Earth and in the solar system, and far out across the galaxy."

VOA: standard.2010.04.16

Diamonds are made of carbon, after all--the fourth most common element in the solar system.

FORBES: Fracture Lines

So there are eight planets in the solar system, not nine and not 10.

NPR: Pluto, the Un-Planet?

It also found that Ganymede, the largest moon in the solar system, has a magnetic field.

ECONOMIST: Galileo and Jupiter