Like a snowplow in overdrive, a supernova shockwave might sweep away any gas clouds in its path.

Photons are accurately and legitimately described as waves and particles at the same time. They are genuine wavicles.

It's my duty to enlighten people.

NASA was invented as a response to Cold War steps. There are those who presumed that we went to the moon because we're explorers. We went to the moon because we were at war with the Soviet Union. And so when it became clear that they (Soviet Union) were not going to the moon, we're done with the moon.

For me, the most fascinating interface is Twitter. I have odd cosmic thoughts every day and I realized I could hold them to myself or share them with people who might be interested.

There are countless space activities that would be no less exciting than the moon missions were, I have no doubt. The search for life on Mars, for example.

Astronauts are the only kind of celebrity I know who can have a line of people waiting for their autograph, even if the line of people does not know in advance the astronaut's name.