According to one classic theory, the reason is simply that there is more habitable space around the equator than at the poles. On the face of it, this seems to make sense.

据常规判断，赤道地带比两极有更多的栖息地，表面上看这个原因很是合理。

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In order to give the top floor more habitable space, we created a mansard roof with three openings.

为了给顶层更多居住空间，我们创建了有三个开口的双坡屋顶。

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The roof is separated from the ceiling of the habitable space to allow for constant ventilation and keep the heated material away from the interior, further helping to cool the space.

屋顶被居住空间的天花板隔开，允许持续通风并将吸热的材料远离室内，进一步帮助冷却空间。

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There is no use in exploring the space and trying to find new habitable space and resources unless we do not try to maintain the balance of nature.

BBC: Is space exploration a waste of money?

However, since Ares I is capable only of reaching low Earth orbit and the space station is the only habitable thing in low Earth orbit, Ares I by itself would be a road to nowhere.

ECONOMIST: Science

This past December, for example, NASA's Kepler space telescope confirmed its first planet in the habitable zone, a "super Earth" known as Kepler-22b that's thought to be 2.4 times as wide as our planet.

MSN: Does 'potentially habitable' alien world exist? - Technology & science - Space - Space.com | NBC News