I remain fearless of airplanes after 9/11. But during a trip to Los Angeles on a Boeing 767, I couldn't keep my mind from drifting: What's the largest piece of this airplane that could crash into the World Trade Center, explode out the other side, and survive intact? The landing gear? My computer battery? My belt buckle? My wedding ring?

Space in general gave us GPS - that's not specifically NASA, but it's investments in space.

When provoked, the itsy-bitsy invertebrates known as tardigrades can suspend their metabolism. In that state, they can survive temperatures of... 73 K for days on end, making them hardy enough to endure being stranded on Neptune. So the next time you need space travelers with the right stuff, you might want to choose yeast and tardigrades, and leave your astronauts, cosmonauts, and taikonauts at home.

If you get asteroids about a kilometer in size, those are large enough and carry enough energy into our system to disrupt transportation, communication, the food chains, and that can be a really bad day on Earth.

Going into orbit around Earth - where the space station is today, and where the space shuttles and John Glenn and all those folks go-that's three-eighths of an inch above a schoolroom globe, just FYI. That's not very far from Earth. Yes, you are off Earth, but you're not really going anywhere yet. The moon was the only real destination.

I think everyone should have a personal mission to leave the Earth a better place for them having lived in it and let Earth then take it from there.

In five billion years, the sun will expand and engulf our orbit as the charred ember that was once Earth vaporizes. Have a nice day