Monadnock Ledger-Transcript
Published: 7/6/2016 7:40:52 PM
The use of the camera and the spectrometer revolutionized the field of astronomy. What they have been able to capture has led scientists to proof of the continuing expansion of the universe.
And but for enterprising amateurs, these tool might never have found their place in the field.
During his talk “Starlight Detectives: How Astronomers, Inventors, and Eccentrics Discovered the Modern Universe,” during the Monadnock Summer Lyceum in Peterborough on Sunday, Dr. Alan Hirshfeld detailed some of the early innovators who brought the camera and the spectrometer to the fore of the astronomy field.
The camera was first developed in 1840. So why, posed Hirshfeld, did it take until 1890 for it to be applied the profession of astronomy?
“In 1840, the professionals are very comfortable sitting at their telescope with their eye. When new technology comes along, they have no interest. So, it is left to the amateurs,” said Hirshfeld.
Taking photos of celestial objects at the time was difficult, said Hirshfeld, because it took a long exposure to take a decent picture, and in that time, there had to be some compensation for the movement of celestial objects.Also, at that time, the field of astronomy had little to do with capturing images of space, and more to do with precisely locating celestial bodies and mapping stars.
But that did not stop those with new technology hot in hand from conducting their own experiments.
In the mid 1840s, John Adams Whipple, a Boston photographer, walked up to Harvard, which had the largest refractor telescope of its day, and asked if he could take a photo through the telescope.
He captured images of the star Vega, the first high quality pictures of the moon and the first photo of a planet – Jupiter.
“This would never happen today,” said Hirshfeld.
But Whipple’s photographs were some of the early examples of what could be done with a camera and the telescope.
Lewis Morris Rutherfurd photographed star clusters and invented a tabletop machine that measured the distance between stars on the photo plate.
In the 1880s, Isaac Roberts had a telescope made just for photographs and took panoramic photographs of the Andromeda Nebula. And ten years later, astrophysicist James Keeler, working with the same telescope, took the first photographs that showed spiral wisps of light – the first images of other spiral galaxies, a discovery that finally galvanized professional astronomers to add the camera to their regular equipment.
The spectrometer, too, was slow to gain popularity among professionals. Until Robert Bunsen and Gustav Kirchhoff discovered that by examining the spectrum of the sun and other stars and comparing it to the spectrums given off when they burned certain elements in their labratory, they could determine what elements the stars contained – something that before then could only be speculated.