This was exactly what I experienced in space: immense gratitude for the opportunity to see Earth from this vantage, and for the gift of the planet we've been given.

And in that moment, I was hit with the realization that this delicate layer of atmosphere is all that protects every living thing on Earth from perishing in the harshness of space.

There are many places that are not made for staying,' Heckleck said. 'They are too harsh, too hard, and too far away from whatever you call home. You don't root where you don't have to, unless you're unluck.