Used by a small group of astrologers, Cosmobiology and its principal tool, midpoints, was developed in Germany in the 1920s. Cosmobiologists do not use houses or traditional aspects. Instead, they read charts with the midpoints, or the halfway point between any two planets. The theory is that the midpoint is the place where the energies of both planets unite. The midpoint is also considered a sensitive point in predictive astrology. Cosmobiologists use midpoint “trees,” a listing of the midpoints for an individual chart, and not the contacts made by other planets, which result in what they call “planetary pictures.”