ABSTRACT
Today, more than seven decades since he first laid the groundwork for quantum mechanics, Niels Bohr's spirit continues to animate science. Bohr extended and enormously enriched the vocabulary of physics, but his imprint on modern thought is to be found far beyond the enclaves of science. The little sketch of the Bohr atom-electrons whirling around a nucleus in ring-like trajectories-is universally recognized as a symbol of knowledge and scientific progress. The family of hydrogen has grown since Bohr's time. The family of hydrogen will also be taken to include Rydberg atoms-a species of hydrogen-like atoms-and the very highly charged single-electron atoms that have recently been created. However, at the risk of a family feud, he omits the heavy hadronic atoms that have been created by particle physicists, and anti-hydrogen, whose time is coming, but is not yet here.
