Summer is definitely the time to come to Antarctica. The weather has been a balmy 20 degrees Fahrenheit and the sunlight allows you to go penguin-watching at 3 a.m. if you want to. My first view of penguins was from the helicopter on the way into Cape Royds. Lines of black dots were strung across the sea ice, their movement imperceptible from our altitude. It took a moment to realize there were indeed 5,000 Adélie penguins going about their daily lives here, just seaward of where explorer Ernest Shackleton's hut nestled into the lava-rock cliffs. Walking through the colony (we had a special permit to enter, issued by the National Science Foundation), we found the penguins had little hesitation in checking us out. They would approach, one at a time or in a small cluster, looking sidelong and swaying a bit like a dog sniffing at someone unfamiliar on his front lawn. Mostly, though, they were getting on with chores: turning their Easter-egg sized eggs and nestling them securely in shaggy folds of down and skin on their bellies (a beefed-up version of the brood patch most birds develop during incubation). Filing patiently in and out of the ocean, a half-mile away across the sea ice. And endlessly seeking pebbles of just the right size to shore up their nests, which are made of nothing but rocks, since there are no sticks or grasses around that they could construct the usual sort from. I'm certainly not the first to say they look like toddlers, little knee-high creatures wobbling around on two legs with their flippers outstretched as if for balance. But they're fearless in their approach. They stop frequently to assess their route, then bounce across the ice or clamber up or down steep rock-strewn slopes. If an obstacle comes up past their knees, they gather both feet together, lean forward, and clear it in a single mighty hop. Hugh Powell is on assignment in Antarctica through December. Read about his exploits here.