(WAND) - Ever wonder why Venus is the brightest major planet?  It is relatively nearby to us, but that's not the main reason.  

Astronomers use the term albedo to describe how bright a planet is in absolute terms. Albedo is a comparison between how much light strikes an object, in this case a planet, and how much the object reflects.  The albedo of Venus is close to 0.7, meaning it reflects about 70% of the sunlight striking it.

Venus has a high albedo because it’s blanketed by highly reflective clouds. The clouds in its atmosphere contain droplets of sulfuric acid, as well as acidic crystals. Sunlight bounces easily off the smooth surfaces of these droplets and crystals, which is a big part of why Venus is so bright. 

By the way, Venus isn’t the most reflective body in our solar system. That honor goes to one of Saturn's 274 know moons; Enceladus. This little moon’s icy surface reflects 90% of the sunlight striking it.Â