Constellation Program

I remember NASA used to have so called "constellation program" several years ago. Briefly, they were planning to send human beings to the Moon again.

This program seems the preparation to build a stronghold on the Moon for the space exploration of the further celestial bodies. The gravity on the Moon is less than 20% of that of the Earth. If some resources are available there, people can build a base and launch rockets by using less energy. The Moon has the potential to be a gate way to deep space.

But this program was canceled because of its huge cost. You know sending humans requires more cost and technologies rather than sending machines. However, this means autonomous systems can play an important role on the efficiency of exploration. In addition, sophisticated autonomous technologies will also reduce the cost of manned exploration in the future. I think the current trend in space exploration is an unmanned autonomous spacecraft. So robotics will gain more focus in the future. (yet, already?)