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Mother of Landsat

2 min · 6. kesä 2026
jakson Mother of Landsat kansikuva

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Have you ever seen those beautiful satellite images of Earth and wondered what camera could take them? The answer is no camera could. They’re produced by a multispectral scanner developed in the 1950s at Hughes Aircraft by a team led by the young MIT scientist Virginia Norwood—known today as the “Mother of Landsat.” Landsat, Earth-imaging satellites, were first launched in 1972 by NASA with the goal to survey the Earth’s surface in real time. The orbital path was set from pole to pole, and they could circle Earth several times a day, taking a full image of Earth every 18 days. But how would they take that image? RCA developed a television-like system using camera lenses recording to early black and white video. But Norwood’s team had a different idea. They captured light reflected from Earth, from within and outside of the visible spectrum, and separated it into multiple electromagnetic bands. They analyzed Earth’s surface using the different properties of each band. Finally, the bands were composited into an image. Early satellites carried RCA’s and Norwood’s systems, but hers quickly won out and became the standard for satellite imaging, now covering Earth every eight days. Norwood continued to advance the field for her entire career, until she retired in 1989—a pioneer whose work is used daily in agriculture, forestry, fisheries, geology, cartography, military applications and many other fields.

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