A battery by definition is a collection of cells. So the cell is a little can of chemicals. And the challenge is taking a very high-energy cell, and a large number of them, and combining them safely into a large battery.

I would like to fly in space. Absolutely. That would be cool. I used to just do personally risky things, but now I've got kids and responsibilities, so I can't be my own test pilot. That wouldn't be a good idea. But I definitely want to fly as soon as it's a sensible thing to do.

It was obvious to me that we could never colonize Mars without reusability, any more than America would have been colonized if they had to burn the ships after every trip.

Actively seek out and listen carefully to negative feedback.

If you're trying to create a company, it's like baking a cake. You have to have all the ingredients in the right proportion.

I think that's an important thing to do, to really pay attention to negative feedback, and solicit it, particularly from friends. This may sound like simple advice, but hardly anyone does that, and it's incredibly helpful.

If anyone has a vested interest in space solar power, it would have to be me.