A substance is anhydrous if it contains no water, for example, salts lacking their water of crystallisation. The way of achieving the anhydrous form differs from one substance to another.
A partial solar eclipse at its peak at 3:37 p.m. in Mesa on Oct. 23, 2014. The eclipse was visible over most of North America and covered 44 percent of the Arizona sun. Michael Chow/The Republic.
August 7: Partial lunar eclipse. August 21: Total solar eclipse. Get ready for a total solar eclipse visible from continental U.S. in 2017. Itâll happen on Monday, August 21, 2017 â with the path of totality cross from coast to coast â the first total solar eclipse visible on U.S. soil in a generation.