Have you seen a gorgeous red sky in the evening, just after sunset? If it’s cloudy, the effect becomes even more spectacular.  The Sunlight reflects off the clouds and back down to the ground, creating the calm of twilight.  Clouds only go so high, so as the Earth continues to turn and we go deeper into nighttime, the glow disappears.  But sometimes it sticks around a bit longer. During a rocket launch at dusk, the exhaust trail from the rocket climbs into the upper atmosphere, far above cloud layers.  It can reflect sunlight, with the shape of the particles refracting...