The black holessink to the centre of the cluster, where a core that is completely made of up of black holes forms.
黑洞向星团中心沉降,在这个区域,形成了一个完全由黑洞组成的核心。
2
If the rock is porous — has many small holes in it, like sandstone — water will sink through these holes until it reaches a layer of rock that is not porous.
As the water level drops, large sinkholes appear along the shores (undermining infrastructures such as roads and Bridges) and farming lands are full of cracks.