We need to understand the Sun
Our unknown solar system
Voyager 1 has finally reached the frontier of interstellar space. The fact that a man-made object is now approaching the heliopause, where the solar winds cease to blow, is a remarkable achievement. Looking back whence it came, the little space probe sees a system that humans have just begun to explore and understand. The biggest and most important unknown is at the center of it all, our local star, the Sun.
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Some claim that the exploration vision requires that NASA give up its space science objectives in order to concentrate on building systems such as the CEV. In fact, it is logical to assume that understanding the solar system environment is just as important to the vision as building the next generation of manned spacecraft.
Everything I need to know I learned through Googling.