Percival Lowell and the Canals of Mars

Tuesday 16th July 2013

  Image of Mars with canali.

Our speaker, Dr Ann Bonell, opened her talk entitled "Percival Lowell and the Canals of Mars" by telling us an anecdote about the fated Beagle 2 mission. It seems that the Control Room for the ill-fated spacecraft that disappeared mysteriously when attempting a Martian landing was sited at the National Space Centre in Leicester. There was even a window that the public could look through and watch the proceedings and next to the window a door. On the door someone had placed a notice that read "hindsight not welcome here". Obviously, once the mission had gone disastrously wrong, the engineers and scientists who had worked tirelessly on the project with a tiny budget did not want to hear any more "told you so" comments from anyone.

Dr Bonell mentioned this rather sad but amusing notice as the main character of her talk, Percival Lowell, has been rather derided for his insistence that he saw artificial canals on Mars that he insisted must have meant it was inhabited. Having a somewhat charismatic personality it is easy to understand how people were convinced by his theories. For the Italian astronomer Giovanni Schiaparelli had previously observed naturally-occurring linear features on the planet which he called "canali". Unfortunately, these lines were mistranslated from the Italian as "canals" and Lowell embellished them in his book "Mars" adding regions and even oases.

After Lowell's death in 1916, due largely to observations by the Italian astronomer Vicenzo Cerulli, consensus grew amongst astronomers that the canals did not exist and were purely optical illusions. In fact, it has been suggested that the patterns Lowell saw do bear a striking similarity to the shapes and lines of retinal vascular patterning.

A more generous way to remember Percival Lowell would be as the founder of the Lowell Observatory in Flagstaff, Arizona and for his predictions that led to the discovery of the dwarf planet Pluto fourteen years after his death. He thought that there was another planet (Planet X) beyond Neptune as this planet and the other "ice giant", Uranus, were being perturbed from their predicted orbits by an unseen body.

In fact Lowell Observatory records show that someone did photograph Pluto in March and April 1915 but did not realise it at the time. It was not until 1930 that Clyde Tombaugh, whilst working at Lowell Observatory, found Pluto near the location predicted for Planet X. However, later on, it turned out that Pluto was too small to have any effect on the orbits of Neptune and Uranus and the orbital discrepancies were due to an incorrect estimate for Neptune's mass. In 1989 Voyager 2's flyby of Neptune gave scientists the correct value.

When he died "Uncle Percy" (as the observatory staff refer to him) was buried on the site of Lowell Observatory. His observatory is still being used today by researchers as well as being an educational/tourist attraction. The site also now houses the Discovery Channel Telescope which is the fifth largest telescope in the continental United States with cutting-edge technology.


This article was written for the club news column of the Stratford Herald. The actual lecture explained the subject at a deeper level.