A Matter of Scale
Astronaut photography awoke many people—including scientists—to large-scale Earth events and planetary rhythms that few knew were going on. One of those events was the destruction of tropical rainforests by fire and blade.
(NASA photograph STS41D-40-22.)
The top image, taken August 31, 1984, from the shuttle Discovery, gives an oblique view of smoke billowing from multiple fires in the Amazon rainforest in Rondonia, Brazil. Farmers and ranchers opened up lands by setting fires in the dry season to make room for cattle and crops. Near the horizon, the Andes Mountains of Bolivia provide a natural barrier so that smoke does not reach the altiplano of southern Peru and Bolivia.
The continent-size scale of slash-and-burn forest clearing was largely revealed to ecologists by astronaut photography. Kam Lulla recalls more than one astronaut marveling at the vast extent of seasonal fires and smoke across the Amazon and many other tropical regions.
(NASA photograph STS046-88-23.)
The lower image, taken from shuttle Discovery on August 2, 1992, looks straight down on the forest to reveal the fishbone pattern of forest destruction. The first clearings in the forest are arrayed along the edges of roads. Over time, legal and illegal roads penetrate a remote part of the forest, and farmers migrate to the area to claim land along the road and clear some of it for crops.
Before astronauts rode into space, scientists and everyday citizens had hints that their world was changing. From space, the scale and the connectedness of the changes become clearer.
Related Reading
- Helfert, M. R. and K. P.Lulla, (1990) Mapping Continental-Scale Biomass Burning and Smoke Palls over the Amazon Basin as Observed from the Space Shuttle. Photogrammetric Engineering and Remote Sensing, 10(56): 1367-1373.
- NASA Earth Observatory (n.d.) World of Change: Amazon Deforestation.
- NASA Earth Observatory (2001, September 2) California Wildfires as Seen from the Space Shuttle.
- NASA Earth Observatory (2002, January 27) Shrimp Farms and Mangroves, Gulf of Fonseca.
- NASA Earth Observatory (2001, April 8) Mount Kilimanjaro's Receding Glaciers.
- NASA Earth Observatory (2001, March 25) Kilimanjaro--The Shining Mountain.

