Alexander Wilson was educated at the University of St Andrews. After this he was an apprentice to a surgeon in St Andrews, then he moved to London. In 1739 he returned to St Andrews and, in 1742, he set up a type foundry. Two years later he moved to Glasgow where, in 1760, he was appointed to the chair of astronomy, a post he held until 1784.
Wilson made many observations of sunspots using a geometric argument to show that they were depressions in the Sun. A similar theory had been proposed by La Hire and by Cassini.
Wilson also published Thoughts on General Gravitation (1770), in which he attempted to answer Newton's question
What hinders the fixed stars from falling upon one another.
Wilson's answer, that the entire universe rotates about a centre, is of course incorrect.
He was awarded an honorary degree by the University of St
Andrews in 1763 and was a founding member of the Royal Society of Edinburgh.