The phenomenon you might be thinking of is a total lunar eclipse, where the moon appears red. This happens when the Earth passes directly between the sun and the moon, casting its shadow onto the lunar surface.

While the moon is in the Earth's shadow, it doesn't go completely dark. Some sunlight still reaches the moon, but it has to pass through Earth's atmosphere first. The atmosphere filters out most of the blue light, leaving the longer wavelengths of red light to reach the moon and make it appear red.

However, there was no total lunar eclipse on August 18, 2008.

To find out when a total lunar eclipse occurred, you can check online resources like the NASA website or a reputable astronomy calendar.