Decide in your heart of hearts what really excites and challenges you, and start moving your life in that direction. 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. Look at who you want to be, and start sculpting yourself into that person. You may not get exactly where you thought you'd be, but you will be doing things that suit you in a profession you believe in. Don't let life randomly kick you into the adult you don't want to become.

Other anatomical changes associated with long-duration space flight are definitely negative: the immune system weakens, the heart shrinks because it doesn't have to strain against gravity, eyesight tends to degrade, sometimes markedly (no one's exactly sure why yet). The spine lengthens as the little sacs of fluid between the vertebrae expand, and bone mass decreases as the body sheds calcium. Without gravity, we don't need muscle and bone mass to support our own weight, which is what makes life in space so much fun but also so inherently bad for the human body, long-term.

Do your homework in advance about the actual travel details so transportation issues do not define your holiday.

Most budget airlines anywhere in the world are going to leave you dissatisfied after using them.

I guarantee if you walk into 100 spider webs, you will have changed your fundamental human behavior. And you can apply this to anything, And figure out a way to reprogram yourself, to change your primal fear.

In my experience, fear comes from not knowing what to expect and not feeling you have any control over what’s about to happen. When you feel helpless, you’re far more afraid than you would be if you knew the facts.

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.