The Earth in Living Color

By Frederic Golden

As Landsat 4 struts its stuff, a debate arises about its future

With their splashes of strong color and rectilinear features, they look like the canvases of a painter. In fact, the pictures are a new form of art, of the high-tech kind. Photographed from 440 miles out in space, they are views of the earth by the U.S.'s newest and most versatile earth-observing satellite, a multieyed robot called Landsat 4. Launched last July, it has been faithfully circling the globe, swinging from pole to pole and back again once every 98.9 minutes, taking electronic shots of every spot on the planet, except a small region around the poles. These images are a source of information about crops and forests, oceans, mineral resources and the atmosphere.

On Jan. 31, NASA turned over formal control of the Landsat program to the National Oceanic and Atmospheric Administration, an arm of the Department of Commerce, which also runs the U.S. weather satellites. Last week NASA officials released a portfolio of Landsat images, three of which are shown on this page. As NASA's Landsat program manager, Harry Mannheimer, put it, "We can look down through a column of air and see the world."

Unlike spy satellites, such as the Pentagon's Big Bird or the Soviet Union's ill-fated Cosmos 1402, Landsat is not designed to ferret out hidden missiles, spot military movements or read the license plates on Kremlin limousines. Its strength lies in its ability to record panoramic views of large swatches of the earth in a multiplicity of colors, some of them beyond the range of human vision. Returning to the same site every 16 days, it can sound the alarm to changes in the health of crops, spot flows of pollutants into bodies of water, or track sulfur-laden clouds from fuming volcanoes.

Landsat's electronic eyes scan patches of the earth's surface 115 miles square, one after another. (It takes 30,000 images to show the entire planet.) The satellite views each square in different colors, some seven different wave lengths in all, including several "invisible" infra-red frequencies. The images are sent as a stream of radio signals to earth stations, where they are assembled by a computer into full pictures. In many instances, scientists arbitrarily choose the final colors to represent a specific condition; for example, blazing red might indicate healthy crops, while black would mean ailing ones.

To help Third World countries put Landsat data to good use, the U.S. has trained some of their citizens to read the photographs and helped them erect ground stations to receive data directly. The Brazilians have used Landsat to reroute segments of their trans-Amazon highway around swamps and other obstacles. Anyone can purchase the photographs. Even the U.S.S.R. and China have bought them, sometimes of each other's terrain. Indeed, the program has been so successful in spotting resources--copper deposits in Pakistan, tin in Bolivia--that some nations have condemned the orbital photography as economic spying.

Landsat's future is uncertain. The Reagan Administration has refused to launch additional Landsats (cost: $300 million each) beyond one satellite in 1985, when the current instrument is expected to cease functioning. The President wants commercial interests to take over Landsat as well as the nation's weather satellites. Critics point out that private operators would be working with a huge built-in subsidy. More than half of the Landsat output has a guaranteed buyer: the U.S. Government. Meanwhile, France, the Soviet Union and Japan are planning to launch earth-resources satellites, competing in the same market as the U.S. for customers who want dazzling pictures from space.

--By Frederic Golden. Reported by Jerry Hannifin/Washington

With reporting by Jerry Hannifin This file is automatically generated by a robot program, so viewer discretion is required.