If the Earth-Sun distance were as little as 1 percent larger, runaway glaciation on Earth about 2 billion years ago would have caused the oceans to freeze and remain frozen to this day.
If the Earth-Sun distance were as little as 1 percent larger, runaway glaciations on Earth about 2 billion years ago would have caused the oceans to freeze and remain frozen to this day.
如果地球与太阳的距离再大1%，大约20亿年前地球上失控的冰期就会导致海洋冻结，并一直冻结到今天。
3
This newest planet, No. 5, resides in the habitable zone, about 0.8 Earth-sun distances from its star.