７８ Future of space exploration【Space Travel】Dialogue with the Universe
・September 2011, NASA announced a new rocket development program as a replacement for retiring the space shuttle.
・Development costs of the large projects is $ 10 billion.
• The new rocket will be completed in 2017, conduct a manned exploration of asteroid
in 2025, and in the 2030s is a goal of carry the human race to Mars.
Source: National Geographic News
・I think that challenges in rocket development would be to build a system that can be recovered some development costs by space factory or resource exploration, rather than manned and unmanned.