Mars

Among Schiaparelli's contributions are his telescopic observations of Mars. In his initial observations, he named the"seas" and "continents" of Mars. During Italy's "Great Opposition" of 1877, he observed a dense network of linear structures on the surface of Mars which he called "canali" in Italian, meaning "channels" but mistranslated as "canals". While the latter term indicates an artificial construction, the former indicates the connotation that it can also be a natural configuration of the land. From this incorrect translation, various assumptions about life on Mars derived, as the "canals" of Mars soon became famous, giving rise to waves of hypotheses, speculation and folklore about the possibility of life on Mars. Among the most fervent supporters of the artificial canals was the famous American astronomer Percival Lowell who spent much of his life trying to prove the existence of intelligent life on the red planet. Later, however, with notable thanks to the observations of Italian astronomer Vicenzo Cerulli, scientists ascertained that the famous channels were actually mere optical illusions
In his book Life on Mars, Schiaparelli writes: "Rather than true channels in a form familiar to us, we must imagine depressions in the soil that are not very deep, extended in a straight direction for thousands of miles, over a width of 100, 200 kilometers and maybe more. I have already pointed out that, in the absence of rain on Mars, these channels are probably the main mechanism by which the water (and with it organic life) can spread on the dry surface of the planet.