I put up my thumb and it blotted out the planet Earth.

It doesn't sound like there was time for the word to be there. On the other hand, I didn't intentionally make an inane statement... certainly the 'a' was intended, because that's the only way the statement makes any sense.

Research is creating new knowledge.

All in all, for someone who was immersed in, fascinated by, and dedicated to flight, I was disappointed by the wrinkle in history that had brought me along one generation late. I had missed all the great times and adventures in flight.

The regret on our side is, they used to say years ago, we are reading about you in science class. Now they say, we are reading about you in history class.

In flying, the probability of survival is inversely proportional to the angle of arrival.

The [Moon] surface is fine and powdery. I can kick it up loosely with my toe. It does adhere in fine layers like powdered charcoal to the sole and sides of my boots. I only go in a small fraction of an inch, maybe an eighth of an inch, but I can see the footprints of my boots and the treads in the fine sandy particles.