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.
As if the 2017 event isn't remarkable enough, the very same parts of southern Missouri and Illinois will see a second total solar eclipse on April 8, 2024! The two paths of totality intersect very near Carbondale, IL.