Two minutes after liftoff we’re hurtling along at six times the speed of sound when the solid rocket boosters explode off the vehicle and we surge forward again. I’m still completely focused on my checklist, but out of the corner of my eye, I register that the color of the sky has gone from light blue to dark blue to black. And then, suddenly, calm: we reach Mach 25, orbital speed, the engines wind down, and I notice little motes of dust floating lazily upward.
