What the researchers found deep in the lunar interior: a solid iron ball 300 miles across, wrapped in molten iron another 56 miles thick, topped with a 93-mile layer of partially molten material.

研究人员发现在月球内部深处：有一个跨度约为300英里的固体铁球，包裹在另外56英里厚的铁水里，顶上部分地还有93英里层的熔融材料。

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Then from the 19th Century there is an early example of a manufactured iron nail, and from the English Civil War, a solid cannon ball.

然后有一个来自19世纪的早期例子——一个工业化制造的铁钉，还有来自英国内战时期的加农炮弹。

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It will tell you, say that you have a very small solid, I don't know like a ping pong ball in your flow, it tells you how it is going to start rotating.

假定你有一个小固体，比如说，流速场中的乒乓球，它会告诉你，乒乓球是怎样开始旋转的。

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The first pictures of Earth taken from space showed a solid ball covered by brown and green landmasses and blue-green oceans.

VOA: special.2011.01.04

Man of the match Byrne enjoyed a solid display under the high ball against the Azzurri and produced a successful tactical kicking game.

BBC: Byrne hails Ospreys coaching duo

On the foot, the first sensation of a Bemer shoe is the solid balance between heel and ball--and this in a ready-to-wear model.

FORBES: The Sole of Stefano Bemer

Scotland started nervously with Italy dominating the early exchanges through a combination of a solid scrum and the willingness to run the ball out of trouble.

BBC: Italy 23-20 Scotland