哪颗行星是太阳的第七颗行星？

Which is the seventh planet from the Sun?
Uranus is the seventh planet from the Sun. It is made of gas. The methane gas gives vivid blue color. Because it’s tipped, Uranus has seasons that last 20 years. The temperature is almost always the same whether its winter or summer because the planet is so far from the sun. Uranus has 27 known moons.
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