Stars twinkle and sometimes appear to move around due to our atmosphere “scrambling” their light as it travels to our eyes. Stars scintillate, or twinkle, more or less based on a few factors. These include stars’ apparent brightness and their altitude in the sky. Brighter stars appear more affected by this phenomenon, while stars closer to the horizon appear to twinkle more often than stars overhead because you’re observing them through more air. Credit: Astronomy: Roen Kelly One night I noticed a star changing colors and moving perceptibly. But through binoculars, a few dimmer stars in the same field appeared steady. The behavior continued throughout the night, but not a couple of nights later. Why? Allan Hawkinson  Carlsbad, New Mexico You’re absolutely right that stars twinkle — and sometimes appear to move around — due to our atmosphere “scrambling” their light as it travels from the top of Earth’s atmosphere to the ground.…