Many countries, including Iran, are embracing nuclear power as a source of electricity. But just weeks ago, a massive earthquake in Japan caused significant damage to one of that country’s nuclear power plants. While the international nuclear power industry says it is strongly focused on safety, the events at Japan's Fukushima facility raise concerns that - no matter how carefully designed these nuclear facilities may be - accidents can happen. In this first segment of a multi-part series, VOA's Jeffrey Young reviews some of recent history's significant nuclear power mishaps.