The Twilight Saga stars an acrobat.
  As observed from the Earth (see apparent magnitude), sky-gazers know Venus, the brightest planet, as the "morning star" or "evening star" because they can see it during civil twilight
 The apparent travel of the Sun occurs at the rate of 15 degrees per hour (360 per day), but sunrise and sunset happen typically at oblique angles to the horizon and the actual duration of any twilight period will be a function of that angle, being longer for more oblique angles

