Stars From the Ground Floor

The Window at Saint-Paul

Eli: Late May or early June, 1889. Saint-Rémy, in the south of France. Before dawn, Vincent van Gogh is at his east-facing bedroom window in the Saint-Paul-de-Mausole asylum. He tells his brother Theo about it in a letter: 'This morning I saw the country from my window a long time before sunrise, with nothing but the morning star (Venus), which looked very big.' In The Starry Night, there's a big bright star just right of the cypress.

Mara: And the question someone sent in: did astronomers just figure out the exact night sky that inspired Van Gogh's Starry Night? It's Tuesday, October 27th, and today's angle is the collision between forensic astronomy and artistic memory.

Eli: Last week the headlines named a date. We'll take that date back to his window, to his own letters, and to the part nobody has settled. It starts with where he painted. He was a voluntary patient in a former monastery, and he painted indoors, by day, in a ground-floor studio.

Mara: The most famous night sky in art.

Eli: And physicist José Luis Aragón says that's why the sky is likely 'a composite of many nights.' Whether the canvas holds one real morning or a sky put together indoors is the open thread, Mara.

The June Record

Mara: The painting's date rests on one letter from mid-June.

Eli: Around June 18, he writes to his brother again. 'At last I have a landscape with olive trees, and also a new study of a starry sky.' That's the line. Art historians have long dated The Starry Night to mid-June 1889 because of it, just weeks after he checked into the asylum.

Mara: That's a lot to hang on it.

Eli: And this one broke his habit. He liked working outdoors. The Starry Night came from memory. It shows in the village. The Van Gogh Museum says that valley village is imaginary. In the 1980s, an art historian who studied the painting's sky conceded Van Gogh took real liberties with dimensions, and even put in a church that couldn't be seen from his cell.

Mara: So the ground is partly invented. That leaves the sky as the test.

Eli: If the sky is real, it should match June.

Mara: It doesn't, starting with the Moon. The painting has a sharp, thin, waning crescent. On June 19, 1889, the real Moon was waxing gibbous, more than half lit. Aragón calls the mismatch 'a real puzzle.'

Eli: And that didn't stop people from trying to read the stars.

Mara: That same art historian teamed up with an astronomer to rebuild the sky over Saint-Rémy. He used Venus as his anchor, matched it against planetarium reconstructions, and read three painted stars as the constellation Aries on June 19, 1889, the day he took Vincent's excited letter to have been written. The big central swirl he read as an imagined comet. It never became an agreed answer. Testing art against the sky has a name: forensic astronomy. The sky moves on a known schedule, so sometimes it can tell where and when a work was made, or when the event behind it happened.

Eli: So the stars in a picture work like a timestamp, if they're drawn faithfully.

Mara: Right, and Donald Olson built a career on reading those timestamps. He and a colleague worked out that the bright star in Van Gogh's White House at Night had to be Venus, which shone in the June 1890 evening sky. But on Van Gogh's starry skies, Olson has said identifying the stars is 'not simple.'

Eli: An invented village under a Moon that doesn't fit June gives that clock very little to work with.

The July 22 Reconstruction

Mara: Then, on October 22, a paper claimed a sky where the Moon fits.

Eli: It ran in Scientific Reports. The lead author is Elijah Jeong-hyun Kim, an astronomer at Kyung Hee University in South Korea who also runs a telescope company. Their claim: the arrangement in The Starry Night matches the predawn sky over Saint-Rémy on July 22, 1889. That's the date in the headlines.

Mara: July. A month after the letter about a new study of a starry sky.

Eli: Kim came to it his own way. He'd long been fascinated by Van Gogh's art. In 2019 he went to France twice, once in mid-June and once around July 22, to reconstruct Van Gogh's viewpoint. In July he saw brilliant stars rising before dawn that weren't there in June.

Mara: Back at that window, Venus was his star. Kim's asking what rose beside it.

Eli: His answer is the Hyades, a star cluster in Taurus. In his words: 'Previous studies interpreted the celestial objects in 'The Starry Night' as the constellation Aries, but to an observational astronomer's eye they correspond to the Hyades cluster in Taurus.'

Mara: Then they tested the hunch with Procrustes analysis. It's like laying five painted stars over five real ones, then sliding, rotating and resizing one set without bending it, until the outlines line up as well as they can. Whatever's left over is the error. Kim's reason for it: a cluster on canvas 'may be larger or smaller than in reality and slightly tilted.' For the Hyades, the leftover came to about eight percent. That was the best of 120 pairings they tried. And the team found that a later pen drawing Van Gogh made of the scene fits the Hyades even more closely, at about six and a half percent.

Eli: Though that was a copy he drew afterward, not the oil.

Mara: And the Moon from the June puzzle finally behaves. By the team's numbers, at about 3 a.m. on July 22, the Moon was a crescent, about 28 percent lit. Venus and the Hyades were rising in the east. Moon and Venus sat 18.6 degrees apart, almost exactly the diagonal of the painting's frame. What nobody has shown is that Van Gogh stood at a canvas with that sky in mind. Whether an eight percent fit can carry a calendar date is still open, Eli.

Collision with History

Eli: Late July, 1889, Saint-Rémy. A crisis takes Van Gogh down, and he doesn't paint for about six weeks. In a letter that August, he tells his brother it overtook him in the fields, painting on a day of strong wind. Kim's team matched that to a powerful mistral, the fierce northerly wind of the south, blowing in late July. The records are thin, so nobody can date the onset for certain. But on their reading, the dawn of July 22 falls less than a week before he's out of action.

Mara: Which leaves July 22 a very narrow window to paint in.

Eli: And behind it sits the June letter already naming the study, plus a drawing of the composition sent to his brother on July 2, weeks before that dawn. Most historians think it was painted before the illness. Then the surprise. Kim himself says astronomy can't settle the order of brushstrokes or any later reworking. He floats the idea that Vincent conceived it in June and finished after July 22, but adds: 'This is my personal opinion rather than a result of our study.'

Mara: That gives two readings, Eli. Kim and his co-author Ho Jin read a real dawn observation around July 22. Olson, the Van Gogh Museum, the Museum of Modern Art and Aragón read a stylized sky built across several nights.

Eli: And Aragón himself calls July 'an intriguing hypothesis rather than a settled answer.'

Mara: Yongxiang Huang, who was not involved in the study, warns that 'Vincent van Gogh was a Post-Impressionist master, not an optical camera.'

Eli: Aragón grants the other side something too: 'The painting is not pure fantasy. Van Gogh watched the real sky very closely.' What that close watching turned into on the canvas is the piece still to place.

Man Added to Nature

Mara: Set July 22 aside, then. What's left is the canvas itself.

Eli: One real star from that window, and around it: blue and white swirls. Stars wrapped in halos. A luminous crescent, rolling hills, a cypress, that imaginary village. The Museum of Modern Art's account describes a mix of observation and artistic transformation. Kim's team says the work was likely based on real sightings. What neither settles is whether those sightings came from one morning or many.

Mara: Real pieces, rearranged. He said nearly as much himself.

Eli: He did. He described the canvas to his brother as 'an exaggeration from the point of view of arrangement.' And late that November, in another letter, he looked back on it as a misstep. He'd 'allowed myself to be led astray into reaching for stars that are too big—another failure—and I have had my fill of that.' One art historian later summed it up as 'an amalgam of images.'

Mara: The painter himself thought so.

Eli: And physicists have gone after the swirls, not just the stars.

Mara: In 2024, a paper in Physics of Fluids said the swirls follow Kolmogorov's theory of turbulence, the law describing how energy cascades down through swirling air or water. It suggested his brushstrokes captured uneven air movement. In 2025, two fluid dynamicists answered that its conclusions were 'completely unfounded.'

Eli: Even the 2024 author says artists' flows often diverge from physical reality through stylization.

Mara: Another team then found the same mathematical signature in a Degas painting of flowers, with nothing turbulent in it. Their corresponding author put it this way: 'All roses are flowers, but not all flowers are roses.' And the stars have the same problem. Three Andromeda stars fit three painted ones at under one and a half percent, better than the Hyades, simply because any three points make a triangle. Kim notes that different constellations could fit to a similar degree. So the July 22 match is a reconstruction, not a discovery: a July dawn that fits well, on a canvas he'd described in June and painted from memory.

Eli: Kim isn't backing away. 'I am confident that July 22 is the better date. I will bet on this date.' His reason: 'No two skies are the same. Something always changes. I believe Vincent noticed those changes and put them into the painting.'

Mara: The historical evidence suggests Van Gogh synthesized observed dawn skies with invented landscape features in the studio. That window gave him Venus. The rest took shape indoors, by daylight.

Eli: Two things could still shift it. Technical study of the paint layers could show whether he reworked the sky after July 22. And hospital records could pin down when his July breakdown actually began.

Mara: Read up on forensic astronomy.

Eli: And follow culture with us.

Mara: Thanks for spending this time with us. I'm Mara.

Eli: And I'm Eli. Until next time, this has been Angle.