Forensic Astronomer Dates Monet Vision

This is Scientific American 60-Second Space. I'm Clara Moskowitz. Got a minute?
An aspect of Claude Monet's famous painting Impression, Sunrise has long been a mystery.
The canvas depicts pink morning light reflecting off the harbor in the Normandy coast port of Le Havre.
The work gave the Impressionist movement its name, yet scholars have debated exactly where and when it was made.
Now, thanks to Texas State University forensic astronomer Donald Olson, we know the answer: November 13, 1872 at 7:35 a.m.
Monet himself dated the painting to 1872, but records of his travels suggested 1873 might be more accurate.
The hazy colors and loose brush strokes make it difficult to tell the season depicted.
Some art historians even argued that Impression, Sunrise is actually showing a sunset.
Olson analyzed angles and views in vintage photographs and period maps of Le Havre to determine the exact hotel room Monet painted in.
He then calculated the sun's movements as seen from the room, as well as the times of the tides.
This information told him when boats matching those in the painting might have been in harbor with the sun in the right position.
Combining all this data with weather reports, Olson was able to pin down the timing of Impression, Sunrise.
You could say Olson is right on the Monet.
Thanks for the minute, for Scientific American 60-Second Space. I'm Clara Moskowitz.