John J. McCarthy Observatory, New Milford, CT. Monthly astronomy lecture done by Bob Lambert. Date of lecture is October 2008. Lecture starts with explanation that we are now living in the Earth’s Secondary Atmosphere. There was a First Atmosphere called the primary atmosphere and it did not resemble today’s atmosphere at all. The evolution of our atmosphere is a continuum of an evolution, the atmosphere continues to change. The presenter discusses the gases that were contained in the first atmosphere and gases that are contained in the atmosphere today. Then video discusses why it is important to study our atmosphere. Presenter stands beside a screen that is a Power Point presentation. Video is of good quality and would be appropriate for late elementary students through high school students.