• The Lunar Terminator • The dividing line marking the edge between day and night on the moon, shown here rotated 90° to the right. The terminator isn’t fixed on the moon. It creeps across the moon’s surface, with the change in its location noticeable in just hours to those peering through telescopes. A day on the moon lasts 29.5 Earth-days. The moon’s terminator moves a bit slower than 10 miles per hour (16 kph) across the Lunar surface. That pace seems almost glacial when you consider that, fo

The terminator is a moving border that wraps around the Earth as it spins, creating the illusion of the Sun rising and setting. At any moment, one half of the Earth is bathed in sunlight, while the other is in shadow, and the terminator is the glowing boundary in between. But it’s not a hard line. It’s a gradient of light, softened by Earth’s atmosphere. This is why we get beautiful sunsets and sunrises, with the sky glowing long before or after the Sun is visible. Some Facts About The Terminato