... Turner biographer James Hamilton has uncovered compelling evidence that the artist was far more interested in cutting-edge scientific theories than has been thought.

One painting in particular – The Festival of the Opening of the Vintage at Mâcon [Graves Art Gallery, Sheffield] – holds, Hamilton believes, a fascinating secret. The painting, executed in 1803 after Turner travelled through France, is dominated by a ferocious sun, and Hamilton argues that it is painted in an entirely new and revolutionary way, based on scientific theories expounded by the astronomer Sir William Herschel.

Herschel gave a groundbreaking lecture to the Royal Society in 1801, in which he revealed his discovery that the sun had a surface with "openings, shallows, ridges, nodules, corrugations, indentations and pores". [...] Hamilton said Herschel examined the sun through his telescope near Slough, passing the light through watered ink, "and he saw the sun, for the first time, as an object. He saw it had a surface".

Not long after the discovery, Turner was painting the Mâcon festivities and appears to have painted the sun as Herschel had described.

"In a sense you can't really see it, you can't focus on it, but if you look very, very closely there is a tiny little disc which is in three distinct parts," said Hamilton. "They are painted in different ways – there's a dab and a wipe and sort of flick of the brush. He is making it into something, he is giving it a surface and coming so close to Herschel's lecture and his naming of parts, one has to see them as connected events."