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Saturn is 95 times as massive as Earth, yet its average density is about 30% lower than that of water: in an impossibly large bathtub, it would float.

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Saturn is a gas giant, made mostly of hydrogen and helium. It is big enough to hold more than 700 Earths, so its mass is spread through an enormous volume, and its average density works out at about 0.69 grams per cubic centimetre, against 1 for water. It is the only planet in the Solar System less dense than water. The bathtub picture is only a comparison: Saturn has no solid surface, and deep inside, its hydrogen is squeezed into a liquid around a core rich in rock and ice. Saturn also spins fast, once in about 10 and a half hours, and the spin flattens it: it is about a tenth wider at the equator than from pole to pole.

Türkçe oku
Satürn'ün kütlesi Dünya'nınkinin 95 katıdır, ama ortalama yoğunluğu sudan yaklaşık yüzde 30 düşüktür. Onu alacak kadar büyük bir küvet olabilseydi, Satürn suda yüzerdi.

Satürn, çoğunlukla hidrojen ve helyumdan oluşan bir gaz devidir. İçine 700'den fazla Dünya sığacak kadar büyüktür; kütlesi bu dev hacme yayıldığı için ortalama yoğunluğu santimetreküpte yaklaşık 0,69 gramdır, suyunki ise 1 gram. Güneş Sistemi'nde yoğunluğu sudan düşük olan tek gezegen odur. Küvet benzetmesi yalnızca bir karşılaştırmadır: Satürn'ün katı bir yüzeyi yoktur; derinlerde hidrojen, kaya ve buzca zengin bir çekirdeğin çevresinde sıvılaşacak kadar sıkışmıştır. Satürn çok hızlı da döner, bir turu yaklaşık 10,5 saat sürer. Bu hızlı dönüş gezegeni basıklaştırır: Ekvatordaki genişliği, kutuptan kutba uzunluğundan yaklaşık yüzde 10 fazladır.

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Background reading: Saturn
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