Saturday, February 18, 2017

Of Aironauts and Astronauts

I'm always happy when I find an earlier example of remote sensing than I knew about previously. This week I found Baldwin's Airopaidia, a book about observing the earth from hot air balloon, accompanied by wonderful maps of the earth's surface, obscured in places by billowing clouds that lend them a dream-like quality. (Here's an incredibly detailed image from the book.) In his descriptions, Baldwin says "The Imagination itself was more than gratified; it was overwhelmed." [emphasis Baldwin's]. He was fascinated that the River Dee in Wales looks like a "broad red Line" from the air, but silver or black to those on the ground.

Ballooning apparently had a great impact on the way we think about landscapes, possibly something like the "blue marble" image of earth from space has on the imagination today. In the 19th century Gaspard-Felix Tournachon, known as Nadar, took the first photographs of the earth from a balloon (but the word "nadir" comes from the Arabic, not Mr "Tourne-a-Dart"). In the early 20th century, truly "remote" images of the earth were acquired, by cameras were mounted on carrier pigeons, automatically recording images every few seconds. In 1947, we had the first images of earth from space, in which the curvature of the planet was visible.

What's most interesting to me about these developments is what people wanted to see in remotely sensed images of the earth. Baldwin's Airopaidia is so interesting because it really seems motivated by curiosity and wonder. Technological advancements often came from some need, particularly military advancements. With the development of orthophotos, or images in which the perspective view has been removed, it was possible to address more practical concerns like estimating agricultural area or timber stocks. Amusement was a common motivation, and aerial imagery was often used in marketing areas for tourism. Using images of the earth to study ecology and the environment necessarily came later, after these disciplines emerged.

No comments:

Post a Comment