Photo by heathermg UPDATE: Space shuttle Discovery has landed safely at 11:57:17 a.m. Next mission: Smithsonian National Air & Space Museum Just a few moments ago, the space shuttle Discovery started experiencing the first effects of re-entering the Earth’s atmosphere as it returns from its latest mission — its last re-entry before being decommissioned and mothballed. Just 15 minutes away from its last touchdown at Kennedy Space Center in Florida, the shuttle Discovery will…