Study suggests much-loved work was based on a real dawn sky in July 1889 rather than just the artist’s rich imagination

It was long assumed to be a product of Vincent van Gogh’s rich imagination – but scientific sleuthing now suggests The Starry Night may be based on a real dawn sky.

Researchers say the celestial bodies depicted in the famous painting match the sky the Dutch artist may have seen on about 22 July 1889, a month later than the usual date given for the work.

Châtaigniers en fleurs, valued at $180m, to be auctioned along with 11 other works by likes of Cézanne and Monet

For more than 50 years it was held in a private art collection with an “almost mythical status” that was likened to a miniature version of Paris’s Musée d’Orsay.

But on Wednesday a painting by Vincent van Gogh created during the last two months of his life has gone on display before it is put up for auction with a value of $180m (£136m).

From a Van Gogh self-portrait to Gauguin’s dreamscapes, new studies show that seeing original art can calm stress and boost health

In an era characterised by burnout and doomscrolling, a therapeutic alternative is hanging on a gallery wall. When volunteers at London’s Courtauld Gallery stood before Van Gogh’s Self-Portrait With Bandaged Ear, Manet’s Bar at the Folies-Bergère, and Gauguin’s Te Rerioa, their stress and inflammation levels dropped compared with those of volunteers viewing reproductions. Science suggests that original art is a medicine that one can view rather than swallow.

That art can lift spirits is well known. But that it calms the body is novel. A study by King’s College London asked participants to look at masterworks by 19th-century post-impressionists – Van Gogh, Toulouse-Lautrec, Manet and Gauguin – while strapped to sensors. Half the group saw the originals in the gallery, half viewed copies in a lab. The results were clear: going to art galleries is good for you – relieving stress and cutting heart disease risk, as well as boosting the immune system.