Astronomer claims to have pinpointed date of Vermeer's View of Delft

Celestial sleuth' says light and shade show when 17th-century cityscape was painted

He is known as the Sphinx of Delft" as so little is known about him. But courtesy of research by Donald Olson, a professor of astronomy from the University of Texas, a little of the mystery surrounding the life and works of the Dutch master Johannes Vermeer may now have been cleared up.

Vermeer's View of Delft, judged by the French writer Marcel Proust to be the most beautiful painting in the world", is said to be the most famous cityscape of the 17th century. But debate has raged over when it was painted, given the lack of knowledge about the artist's life and times.