You're walking down the street, minding your own business, when you see a snowball. No big deal, right? Except that the snowball is as tall as you are and weighs about a ton. Did we mention that it's June? That's the experience thousands of Londoners had when they crossed paths with "Snowballs in Summer", the brainchild   of artist Andy Goldsworthy. Goldsworthy makes sculpture from all sorts of things he finds outside-leaves, earth, and rocks, as well as ice and snow. He wanted to find out how busy city people would react to an unexpected snowball melting in their midst. During the winter of 2005, he rolled 13 giant snowballs near his home in prefix = st1 /Scotland. He filled each one with a surprise in the center-such as pebbles, berries, feathers, or sheep's wool  which would emerge as the snow melted. The finished snowballs were stored in a deep freeze until summer, then transported toLondonin refrigerated trucks. At midnight on June 21, 2006,   while the city slept, Goldsworthy and his co-conspirators rolled their snowballs into place. People walking to work or school must have thought the sky was falling when they stumbled across snowballs of the size of baby elephants. Some of them had never even seen snow in real life, and they couldn't resist poking   the snowballs or even breaking off a chunk . As the snow started to melt, things got even more interesting. The perfectly round snowballs took on different shapes as the stuff inside began to poke through. Two days later, most of Goldsworthy's snowballs were gone, and their fillings scattered. But Londoners were left with a really good story about that odd summer day when the snowballs came. How long had the snowballs been stored before they were seen?
For about half a year. For 21 days. For about a year. For 13 months.