Boston Globe Online: Van Gogh was keen observer of starry nights - Vincent Van Gogh. The very name evokes the struggle between art and madness. The legendary 19th-century post-impressionist created some of his best-known paintings while confined to a mental asylum, and later killed himself at the age of 37. Yet, for many astronomers, Van Gogh cuts a very different figure. To them, he was a pretty darned good observer of the stars. ''Starry Night'' isn't merely beautiful; it depicts an unusually bright planet Venus in a rare alignment with a thin crescent moon.