- Polygonal, patterned ground is quite common in some regions of Mars. It is commonly believed to be caused by the sublimation of ice from the ground. Sublimation is the direct change of solid ice to a gas. This is similar to what happens to dry ice on the Earth. Places on Mars that display polygonal ground may indicate where future colonists can find water ice. Low center polygons have been proposed as a marker for ground ice. Polygonal terrain is also found on earth’s permafrost.
- Gadsden flag (Wikipedia)
The Gadsden flag is a historical American flag with a yellow field depicting a timber rattlesnake coiled and ready to strike. Beneath the rattlesnake are the words Dont Tread on Me [sic]. Some modern versions of the flag include an apostrophe in the word “don’t”.
