If Jupiter was in the ascendant when you were born, you are of a jovial disposition; and if you're not jovial but miserable and saturnine that's a disaster, because a disaster is a dis-astro, or misplaced planet. Disaster is Latin for ill-starred.The fault, as Shakespeare put it, is not in our stars; but the language is.
Mark Forsyth, The Etymologicon: A Circular Stroll through the Hidden Connections of the English Language
astrology, language, shakespeare, stars