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.

Doing a space walk. It is one of the most rare human experiences. To leave your spaceship and go outside, so that you are alone in the universe with Earth distant and the universe around you. That is amazing.

I've been lucky enough to fly to space twice.

Ultimately, leadership is not about glorious crowning acts. It's about keeping your team focused on a goal and motivated to do their best to achieve it, especially when the stakes are high and the consequences really matter. It is about laying the groundwork for others' success, and then standing back and letting them shine.

Every decision you make, from what you eat to what you do with your time tonight, turns you into who you are tomorrow and the day after that.

Still, I also know that most people, including me, tend to applaud the wrong things: the showy, dramatic record-setting sprint rather than the years of dogged preparation or the unwavering grace displayed during a string of losses. Applause, then, never bore much relation to the reality of my life as an astronaut, which was not all about, or even mostly about, flying around in space.

The Bahamas are gorgeous. The deep trench in the ocean floor called the Tongue of the Ocean, which comes between the islands, is the most beautiful deep indigo colour.