Technology
The satellite carried a single instrument that would have taken the most precise measurements of atmospheric carbon dioxide ever made from space. The instrument consisted of three parallel, high-resolution spectrometers, integrated into a common structure and fed by a common telescope. The spectrometers would have made simultaneous measurements of the carbon dioxide and molecular oxygen absorption of sunlight reflected off the same location on Earth's surface when viewed in the near-infrared part of the electromagnetic spectrum, invisible to the human eye.
As sunlight passes through Earth's atmosphere and is reflected from Earth's surface, molecules of atmospheric gases absorb very specific colors of light. If the light is divided into a rainbow of colors, called a spectrum, the specific colors absorbed by each gas appear as dark lines. Different gases absorb different colors, so the pattern of absorption lines provides a telltale spectral "fingerprint" for that molecule. OCO's spectrometers were designed to detect these molecular fingerprints.
Each of the three spectrometers was tuned to measure the absorption in a specific range of colors. Each of these ranges includes dozens of dark absorption lines produced by either carbon dioxide or molecular oxygen. The amount of light absorbed in each spectral line increases with the number of molecules along the optical path. OCO's spectrometers would have measured the fraction of the light absorbed in each of these lines with very high precision. This information was then to be analyzed to determine the number of molecules along the path between the top of the atmosphere and the surface.
If the amount of carbon dioxide varies from place to place, the amount of absorption will also vary. To resolve these variations, the observatory's instrument was to record an image of the spectrum produced by each spectrometer three times every second as the satellite flies over the surface at more than four miles per second. This information would then have been transmitted to the ground, where carbon dioxide concentrations would have been retrieved in four separate footprints for each image collected. These spatially varying carbon dioxide concentration estimates would then have been analyzed using global transport models, like those used for weather prediction, to infer the locations of carbon dioxide sources and sinks.
The OCO instrument was developed by Hamilton Sundstrand Sensor Systems in Pomona, California, and the Jet Propulsion Laboratory.
Read more about this topic: Orbiting Carbon Observatory
Famous quotes containing the word technology:
“If the technology cannot shoulder the entire burden of strategic change, it nevertheless can set into motion a series of dynamics that present an important challenge to imperative control and the industrial division of labor. The more blurred the distinction between what workers know and what managers know, the more fragile and pointless any traditional relationships of domination and subordination between them will become.”
—Shoshana Zuboff (b. 1951)
“One can prove or refute anything at all with words. Soon people will perfect language technology to such an extent that they’ll be proving with mathematical precision that twice two is seven.”
—Anton Pavlovich Chekhov (1860–1904)
“If we had a reliable way to label our toys good and bad, it would be easy to regulate technology wisely. But we can rarely see far enough ahead to know which road leads to damnation. Whoever concerns himself with big technology, either to push it forward or to stop it, is gambling in human lives.”
—Freeman Dyson (b. 1923)