I visited the Lowell Observatory (1) at Flagstaff, Arizona, on June 29, 2018. Now a National Registered Historic Landmark on Mars Hill just west of old Route 66, the Observatory was founded in 1894 by Percival Lowell. Its primary mission was to study the planets of the solar system with Mars being a particular focus of attention. We arrived just in time to take The Story of Pluto Guided Tour which culminates in the Lawrence Lowell Telescope building. This is the site of discovery of Pluto and houses the astrograph and guide telescope actually used by Clyde Tombaugh in that effort.
The Lawrence Lowell Telescope building where Clyde Tombaugh discovered Pluto
Our tour guide gave us a lively overview of the observations that prompted a systematic search for an unseen ‘Planet X’ as Percival Lowell had designated it. Along with the scientific aspects some history of the interesting characters in the story was provided.
The astrograph was a home-brew affair, built to handle the challenging conditions of wind and weather of Mars Hill. The 13-inch (33 cm) objective optics features a unique triple lens arrangement designed to enable large format plates (photographs) to be exposed. Stanley Sykes and his son Guy constructed the double-anchor point mount and a local carpenter (Mr. Mills) built the dome (2). Clyde Tombaugh, a young man with no formal academic credentials at that time was hired to conduct the arduous search. One of his first jobs to was to finish and paint the new astrograph (2). Although it now sports a shiny metallic gray color, it was once (Mars?) red.
The Lawrence Lowell astrograph and guide telescope used by Clyde Tombaugh
The Path To Pluto Via Mars
An intense fascination with the planet Mars led Percival Lowell to found the Observatory that still bears his name over a century later. Influenced by the writings of astronomers Giovanni Schiaparelli and Camille Flammarion (3), Lowell initiated his own studies of Mars and promoted the hypotheses that this world harbored a living, active biosphere inhabited by intelligent beings (3).
In his lectures, articles and books, Lowell explained how his observations of artificial canals on Mars revealed the story of a drying planet and a civilization responding with an engineering effort of gigantic scale (4). The goings-on of the times were probably inescapable influences and several contemporaneous, large-scale canal construction projects had naturally drawn public attention in Lowell’s day. The War of the Worlds was published a few years after Lowell began his observations and that circumstance coupled with the fact the location names employed by Giovanni Schiaparelli on his Mars maps were evocative and included linear features designated ‘canali’ (3) might have all combined to channel his thinking.
Lowell’s public lectures and 1908 book, Mars as the Abode of Life (4), ignited public interest. His story – based on personal observations made with one of the finest telescopes in the world at that time – was compelling and it made him famous. As a young man with a deep interest in astronomy, Clyde Tombaugh was well acquainted with the ideas of Percival Lowell and considered him a personal hero (2). When Tombaugh sought professional advice on the planetary observations he was making with his hand-built telescope, he wrote to the Lowell Observatory. That decision, perhaps based on perceived kinship with the late Percival Lowell, ultimately changed his life and the institution forever. Tombaugh had no academic training, but possessed a deep love of astronomy along with a meticulous approach to work that enabled him to succeed in the grueling quest to locate Planet X predicted by the calculations of Percival Lowell. Absent Clyde Tombaugh the discovery of the first trans-Neptunian object might have been long delayed (2, 5) and may not necessarily have occurred at the Lowell Observatory.
The Road to Redemption
Lowell extrapolated his observations of Mars surface features into evidence for an advanced civilization coping with adverse changes in planetary climate. Further, he deduced the existence of a global canal system revealed the Aresian political environment was fundamentally different from that of Earth; the Martian engineers obviously believed in cooperation (4).
Percival Lowell already possessed a personal fortune, so he had no financial motive to indulge the fantasies of any audience in order to sell books or pamphlets. The Mars narrative he championed reflected personal beliefs and it made him – as well as his institution – pariahs to many in the professional scientific community (2). A letter published in the journal Science (6) states the issues explicitly. Lowell was accused of feeding pseudo-science to a naïve, but enthusiastic, public. Noting Lowell’s impressive ability to communicate with the general public, the errors, misrepresentation of theories as established fact and lack of supporting data were judged worthy of censure. Allowing that Lowell was discussing his own observations and that it is his privilege to interpret them as he saw fit, the letter author still concluded his actions were deceptive and “immoral.”
Clyde Tombaugh had the opportunity to observe Mars using the same 24-inch telescope once employed by Lowell. Noting that he saw and drew lines like those of Lowell (5), Tombaugh pointed out that many critics were not actually planetary observers. Despite his personal experiences and admiration of Lowell, Tombaugh recognized the realities of the canals of Mars (2, 5).
With so much of the scientific community hostile, Percival Lowell and the Observatory staff were ‘outcasts’ (2). When Clyde Tombaugh arrived at the Observatory over a decade after Lowell’s sudden death, the astronomers were still demoralized due to their ‘ostracism’ (2). Recognizing the discovery of a new planet would be heralded and draw immediate competition, Lowell Observatory managed their formal announcement carefully, well aware of their ‘underdog’ status (5) and the opportunity for professional reputation redemption it would provide.
It is hard to imagine the acclaim and prestige such a discovery would bring. Possibly one of the finest actions ever taken by the Lowell Observatory staff and leaders was the decision to give Clyde Tombaugh – the young man without formal training – full credit for his essential contributions to the successful team effort to find Planet X. Who discovered Pluto? To this day most of us answer ‘Clyde Tombaugh,’ although I bet he would probably have pointed out the journey began with Percival Lowell’s mathematical calculations and the work of observatory staff long before he arrived.
It is recognized that the discovery of Pluto based on Percival Lowell’s mathematical predictions for an unseen Planet X was sheer coincidence. Almost immediately the Lowell Observatory staff and others were concerned that the estimated mass of Pluto was too small to be the cause of the perturbations in the orbits of Uranus and Neptune that launched the effort. During the Story of Pluto Guided Tour, our presenter noted how the astronomical symbol for Pluto, could be interpreted as Percival Lowell’s initials or, more fancifully, as an enshrinement of “Pretty Darn Lucky.”
Driven by his personal interests, Percival Lowell carved out his place in the pantheon of astronomy. Vilified by the scientific community of his time, Lowell and his ideas became famous among the general public. Clyde Tombaugh considered him a personal hero. Could it be that the discovery of Pluto was initially set in motion when Clyde started reading the writings of Lowell and emulating him?
Could works today decried loudly as pseudoscience such as The UFO Hunters program or efforts to find Bigfoot actually be seeding the next generation of scientists? This is not a plea for skeptics to cease their critiques, I believe firmly they must continue their work, point out fallacies and show how a scientist might approach the issues. But perhaps we will allow that some of us, possibly many of us, first start out like Percival Lowell and Clyde Tombaugh with nothing more than an intrinsic deep interest in a topic. The scientific expertise (hopefully) will develop later. A quote attributed to Ray Bradbury (3) sums it up –
“It’s part of the nature of man to start with romance and build to reality.”
The evidence suggests professional astronomer peers held the work of Percival Lowell in generally low esteem. The passage of time has revealed his overall claims regarding the planet Mars were indisputably untrue. Still, they might have captured the imagination of the young Clyde Tombaugh and set the stage for him to make some amazing discoveries.
(1) The Lowell Observatory. https://lowell.edu/
(2) Clyde W. Tombaugh and Patrick Moore. Out of the Darkness. The Planet Pluto. Mentor Books.
(3) William Sheehan and Stephen James O’Meara. Mars. The Lure of the Red Planet. Prometheus Books.
(4) Percival Lowell. Mars as the Abode of Life. Reprinted (2000) by Bohn Press.
(5) David H. Levy. Clyde Tombaugh. Discoverer of Planet Pluto. Sky Publishing Corporation.
(6) Eliot Blackwelder. Letters – Discussion and Correspondence – Mars As The Abode of Life. Science 29:659-661, 23 April 1909. http://science.sciencemag.org/content/29/747/659
For younger readers –
Tony Simon. 1965. The Search for Planet X. Scholastic Book Services.