The Nile, draining out into the Mediterranean. The bright lights of Cairo announce the opening of the north-flowing river’s delta, with Jerusalem’s answering high beams to the northeast. This 4,258 mile braid of human life, first navigated end-to-end in 2004, is visible in a single glance from space.

It's good to have a fear of heights. I mean, it's kind of crazy not to because if you just lean out a little bit and there's a gust of wind or somebody bumps you or something and you fall, you're splat.

Life off Earth is in two important respects not at all unworldly: you can choose to focus on the surprises and pleasures, or the frustrations. And you can choose to appreciate the smallest scraps of experience, the everyday moments, or to value only the grandest, most stirring ones.

Fatherhood is the unending imperfect task of turning yourself into your dad while secretly maintaining the unbridled elation of your boyhood

The rough and ready improvisational quality to life on board the International Space Station is reminiscent of a long trip in a sailboat: privacy and fresh produce are in short supply, hygiene is basic, and a fair amount of the crew's time is spent just on maintaining and repairing the craft.

For the last several years and culminating in six months in orbit next year, I've been training for my third space flight. This one is almost in a category completely different than the previous two, specifically to live in on the space station for six months, to command a space ship and to fly a new rocket ship.

The danger is different from the fear. ... [practice] what to do if things go wrong, as well as right.