In 2015, Wylie Overstreet and his friends endeavored to create a to-scale model of the solar system. The scale they chose centered around a sun the size of a large balloon, surrounded by planets including a marble-sized Earth and a watermelon-sized Jupiter. They traced the orbits of the planets in a patch of Nevada desert, ending up with a solar system that stretched 7 miles (11 km) across from one end of Neptune's orbit to the other. The effort underscores just how difficult it is to accurately envision the size and scale of things in space.