This reference book consists of questions submitted by the public and Odenwald's answers, taken from the author's "Ask the Astronomer" internet website at the Astronomy Cafe. This is a compilation of the Top-100 questions answered at The Astronomy Cafe between 1995 and 2013 from an archive of over 3000, which were requested over 10 million times. The topics range from Higgs bosons and the nature of gravity, to extra solar Earth-like planets and global warming. There is also a collection of tables that include a list of the known nearby black holes, the most distant objects we know in the universe, and upcoming asteroids that may hit Earth. The general reader may find this easy to read reference an enjoyable way to learn about these topics.