By what decade had improved telescope optics and atmospheric understanding caused the perceived canal network to thin out considerably?
Answer
The 1920s and 1930s
As technology advanced and observational techniques improved, coupled with a better understanding of Earth's atmospheric effects, the crisp, linear features Lowell mapped began to disappear from telescopic views during the 1920s and 1930s.
Related Questions
What did Giovanni Schiaparelli originally call the linear features he observed on Mars in 1877?What English word replaced Schiaparelli's original term, carrying a strong connotation of artificial construction?What did Percival Lowell specifically theorize the Martian canals were built for?In what year and location did Percival Lowell establish the Lowell Observatory?By what decade had improved telescope optics and atmospheric understanding caused the perceived canal network to thin out considerably?What phenomenon is sometimes cited as the likely mechanism by which the human brain perceived the indistinct Martian markings as straight lines?What natural Martian features, rather than constructed networks, were revealed by high-resolution images from the Mariner missions?What key methodological contribution did Lowell's extensive, albeit flawed, work provide to planetary astronomy?What did Lowell's detailed seasonal charts track regarding the canals?What was Schiaparelli's original intention behind labeling the features *canali*?