June 09, 2011
The photo above captures the rising full Moon of March 19, 2011 as viewed from just offshore of Sandbridge, Virginia. The Moon looks huge because of the Moon illusion effect and because on this night it was actually considerably closer than an average full Moon. This was the perigee full Moon or "Super Moon" of 2011. Due to its unusually close proximity to Earth, our Moon appeared approximately 14 percent larger than normal -- the largest Moon in about the last 20 years. Its blush color is a result of the greater path length that moonlight takes when the Moon is near the horizon as opposed to when it's overhead. In essence, blue and green colors are scattered from our view when the Moon or Sun hugs the horizon. Note that the Moon isn't a single color. The darker hues, appearing the same color as the Atlantic Ocean, are called "maria," translated into lakes or seas. It's easy to understand why early astronomers believed these were analogous to the Earth's seas. We now know that they're basaltic plains formed by ancient volcanic eruptions.