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Virginia Norwood, who died at age 96, created the multispectral scanning system that flew on the first Landsat satellite in 1972.
The satellites, of which there have been nine to date, continuously observe the Earth and provide invaluable data on processes such as deforestation, urban sprawl and glacier retreat, as well as water quality, crop health, soil moisture and more.
In the late 1960s, during the period of NASA’s lunar missions, the director of the US Geological Survey suggested that photographs of the Earth taken from space could help manage Earth’s resources.
Virginia Norwood, then working at Hughes Aircraft Company, believed that a scanner used for local agricultural observations could be modified for the project and could transmit the information to Earth in digital form.
But he faced skepticism from NASA scientists who preferred an analog system called RBV, which had already been tested on weather satellites. NASA decided to bring both systems aboard Landsat 1 and gave Virginia Norwood a $100,000 budget to develop a prototype.
He went on to design a multispectral scanner (MSS) capable of measuring energy from the electromagnetic spectrum, including visible and infrared light, and incorporating a mirror that mechanically swung from side to side, assembling an image line by line as the satellite was traveling forward.
Landsat 1 went into orbit on July 23, 1972. When spectacular MSS images of the Ouachita Mountains in Oklahoma were broadcast two days later, NASA scientists were amazed. When a power surge later forced the shutdown of the RBV, there was no looking back.
Virginia Monroe Tower was born on January 8, 1927 at Fort Totten in New York to John Tower, an army officer, and Eleanore, nee Monroe. Fascinated by numbers as a child, she read Mathematics and Physics at the Massachusetts Institute of Technology, one of the few female students in “a sea of men”. The day after her graduation, she married Larry Norwood, a graduate student at Yale.
He struggled to find a job to begin with. When you suggested a gun company hire a mathematician to improve quality control, they created a job, but gave it to one man. Another she rejected when she refused to promise not to get pregnant. For a time you worked in a department store.
Things started to look up when she and her husband were offered jobs at the Army Signal Corps laboratories in New Jersey. There she won her first of several patents: for a radar reflector for weather balloons that recorded wind speed at high altitudes.
In 1953 the Norwoods moved to California, where she joined the R&D division of Hughes Aircraft, the only woman among 2,700 employees. In 1957, promoted to lead the microwave group at the company’s rocket laboratory, she became the first woman at Hughes to join the engineering staff.
His arrival caused at least one man to resign in protest; a few years later she reapplied for a job, but she turned him down. When a supervisor acknowledged that while she was the obvious choice to head a newly created department, he “wasn’t willing to appoint a female department head,” she left to join the Space & Communications group, “which proved excellent for me ”.
Among other projects, Virginia Norwood designed the transmitter for the Surveyor spacecraft, which sent images from the Moon in preparation for future Apollo missions. Lei oversaw the development of Landsats 2, 3, 4 and 5 before lei’s retirement in 1989. All Landsats feature scanners based on lei’s original design.
Virginia Norwood’s first marriage was dissolved and her second husband, Maurice Schaeffer, died in 2010. She is survived by one son and one daughter from her first marriage. Another son from her first marriage died in 2012.
Virginia Norwood, born January 8, 1927, died March 27, 2023
