Excessively dense urban layout is not only easy to produce heat island effect, but also does not meet the requirements of ecological aesthetics. 
urban construction should open the layout as far as possible, reasonably interval the city groups, so that the city looks smooth and orderly, not crowded, not cluttered.
The origin of astronomy is roughly at the same time as the origin of civilization. Therefore, the pursuit of the origin of astronomy means that we can grasp the context of the birth and development of civilization to some extent