"And so this time NASA... the Artemis missions are... very much gearing up to go back to the moon. Different setup, different politics... but fundamentally, this time... for the first time in 50 years, we're going to be far enough away to look back at the Earth and to see... this blue planet. And this time we have to see that blue for what it is. ...[T]he timing of the book... from the point of view... of the arc of human history, this time... we have to understand the blue itself, is the point."