- MIRACH (Beta Andromedae). Andromeda’s three brightest stars, Alpheratz, Mirach, and Almach, lie along a graceful curve that extends to the northeast of the Great Square of Pegasus (Alpheratz part of the Square itself).
- Arsenic (Wikipedia)
Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but only the grey form, which has a metallic appearance, is important to industry.