It's Earth Day. More than 40 years ago, a senator from Wisconsin, shaken by witnessing a tragic oil spill off the Pacific Coast and outraged by the lack of concern for such events in Washington, organized a 70's -style "teach-in and celebration" to raise awareness of environmental issues and to engage the public in concern and action around preserving the Earth. That action gave birth to the first Earth Day in 1970. Last year, what was once a grassroots effort was observed by 500 million people in 175 countries worldwide. Earth Day is quite a testament to the power of ordinary folks, just like us, who are interested and concerned with the changes that are happening in the natural world around us.