The first is Civil Twilight. It occurs just before sunrise and just after sunset, when the geometric center of the sun is six degrees below the horizon. During this time, the brightest stars and ...

If you find yourself occasionally checking around for times of sunset, it might never have occurred to you to ask the question: “Just what is sunset, anyway?” Seems like a ridiculous question; ...

Wednesday (Sept. 22) marks the equinox, which, thanks to its Latin name meaning "equal night," is often thought of as the day when dark and light each claim 12 hours. But that isn't the case, and ...