Forensic astronomer solves Walt Whitman mystery

CultureLab: Forensic astronomer solves Walt Whitman mystery

The Meteor of 1860 by Frederic Church (Image courtesy of Judith Filenbaum Hernstadt)

See more: Our gallery of art and other images relating to the 1860 meteor procession

Donald Olson, a physicist at Texas State University, is the world's leading practitioner of forensic astronomy - examining classic works of art and literature that include references to celestial phenomena.

In many of his investigations, Olson and his students use the methods of modern astronomy to determine precisely where and when a particular work of art was created or to pinpoint the event that inspired it. For example, Olson analysed Vincent van Gogh's Moonrise, a painting depicting a glowing yellow orb looming behind the silhouette of a rocky outcrop. Olson was able to determine the exact spot in France from which van Gogh viewed the rising moon, as well as the precise time: 9:08 pm, 13 July 1889.

Olson doesn't restrict himself to painting - he has also examined Ansel Adams's photographs and several astronomical references in literature, from Chaucer's Canterbury Tales to Julius Caesar's account of his invasion of Britain.

I recently spoke with Olson about his latest project - an investigation of Walt Whitman's poem Year of Meteors (1859-60), published in his famous collection, Leaves of Grass. Olson's results have just been published in Sky & Telescope.

Seemingly Intelligent oil droplet solves maze

There's some humbling news from the chemical world for anyone who has ever found themselves lost in a garden maze. A simple droplet of organic solvent can find its way through a complicated labyrinth with nothing more to go on than a slight pH difference.

Bartosz Grzybowski's team at Northwestern University in Evanston, Illinois, used a common polymer to fashion a two-dimensional labyrinth some 2 centimetres on each side. They then flooded the maze with strongly alkaline potassium hydroxide solution, before placing a hydrochloric acid-soaked chunk of gel at the maze exit.

After about 40 seconds they placed a droplet of mineral oil containing hexyldecanoic acid at the maze entrance. The oil, which cannot mix with the potassium hydroxide solution, sits on the surface. But it remains still only for a matter of seconds – it soon begins tearing around the maze at speeds of up to 10 millimetres per second, sniffing out the shortest path to the acid-soaked gel, and solving the maze in the process.

"In the movie files you can see the droplet makes decisions," says Grzybowski. "It goes left along the wrong path, decides there's something fishy with that and so it reverses. It looks almost alive."