Donald Olson is an amateur sleuth, but the mysteries he solves don’t put killers behind bars or reveal the identities of murderers in some sort of overly dramatic third act. No, Olson tackles the mysteries that artists and great figures in history have left for the rest of us to figure out.
The Art Detective
From Atlas Obscura:
An astrophysicist and forensic astronomer, Olson uses quantitative methods to answer questions raised by artwork, literature, and historical accounts—not the heady ones, but the basic, surprisingly slippery who, what, when, and where.
In the past, he and his team at Texas State University have figured out where Julius Caesar landed when he invaded Britain in 55 B.C. (northeast of Dover), why the British didn’t spot Paul Revere as he made his Midnight Ride (the moon was in a weird spot), and the identity of at least two mysterious yellow orbs floating in paintings: the one in Vincent Van Gogh’s “White House at Night” (it’s Venus) and the one in Edvard Munch’s “The Girls on the Pier” (it’s the moon).
Two New Mysteries to Solve
He recently turned his attention to two of Ansel Adams most famous photographs Moon and Denali and Denali and Wonder Lake in an attempt to figure out exactly when and where the images were snapped.
Adams himself was no help in the matter. He frequently didn’t date his negatives and claimed to “rarely be able to recall a date.” In fact, no one could even agree on what year Denali and Wonder Lake had been taken, with sources ranging from 1947 to 1948.
Using the Sky to Solve Mysteries
Olson’s team was confident, however, since they’d had success in solving other Ansel Adams mysteries, and the sky itself has been a huge help. For instance, they’d figure out exactly when and where Adams took his Autumn Moon photo by using the moon’s shape and position.
This technique would only aid them in solving one of the new Adams mysteries since Denali and Wonder Lake showed no objects in the night sky.
Moon and Denali, however, was a different story since there’s clearly waxing, gibbous moon in view through the clouds above the mountain peaks.
From Atlas Obscura:
“We realized that we could use the lunar phase and position of the sky of Moon and Denali to calculate the date of that evening scene,” Olson writes. A look at field notes from Adams, as well as from his son and travel companion, Michael, revealed that Denali and Wonder Lake had been taken the next morning.
To determine these two “whens,” they first had to figure out each “where”: the exact location of Adams’s tripod when he released the shutter. The rippled landscape of Moon and Denali provided clues. “The foreground of [the photograph] includes geological features known as ‘cirques,’ semi-circular steep-sided hollows shaped like amphitheaters,” Olson writes.
Computers Help Determine the Position of Adams’ Camera
Now that they knew they could figure out the “when,” they had to find a way to determine the where. So, playing off the geological features in the foreground of the picture, they compared them to contours on topographical maps of the area, but they didn’t stop there.
They came up with a computer program to help them simulate the view from different points on the map around Denali.
“we wrote a computer program that could calculate the view from any possible spot for Ansel Adams’s tripod,” correcting for refraction and the Earth’s curvature. “Our computer program eventually produced a camera position where the calculated view appeared to match the photograph.”
The First Mystery Solved
They then called up their man on the ground, Jon Paynter, a GIS specialist who works at the park. He traveled to the potential location—a spot on the road about eight miles from the nearest ranger station—and tweaked his positioning until he could reproduce the view himself.
Once they had the location, they used a planetarium software that can reproduce models of the night sky at particular moments in history. Once they had that, they were able to determine that the Adams took his famous photo on July 14, 1948 at 8:28 pm.
A Different Kind of Challenge
For Denali and Wonder Lake, they repeated the process to determine the geologic location, but with no celestial object to determine time of day, they had to use a different technique.
They turned their attention to “the photograph’s deep shadows, which could be used to determine the sun’s position in the sky, and therefore the time of day. Their first round of calculations indicated that the photograph was taken early the next morning, between 3:40 and 3:50 a.m.”
They Get Their Answer
This was not quite exact enough for Olson’s team. So they sent Paynter on a different kind of chase: into the archives of the Denali National Park webcam, which has streamed a view of the mountain for years. They found a different July 15, and checked the shadows at a few different timestamps. As Olson writes, “interpolation allowed us to determine that Ansel Adams tripped the shutter for Denali and Wonder Lake on July 15, 1948, at 3:42 a.m.” The two classic photographs were taken fewer than eight hours apart.
“As a scientist, it makes my life richer to consider great works of art, important historical events, or classic literature,” Olson says, in an email. A little bit of scientific detective work can make the art richer as well. After all, if a photograph makes a moment immortal, it’s nice to know exactly which moment that was.