Nineteenth and early 20th century American astronomer Percival Lowell predicted Pluto's existence (it was discovered in 1930 by Clyde Tombaugh) and founded one of the oldest observatories in the United States.
However, he will probably be best remembered as an ardent supporter of the theory that an advanced alien civilisation irrigated crops on Mars's surface with water drawn from the planet's poles along a canal network.
Historians now believe the canals Lowell mapped were faint surface features or even the product of his imagination.
Photo: Percival Lowell in the observatory he built at Flagstaff, Arizona (Mary Evans Picture Library)
The Pluto searcher sees canals on Mars.
Percival Lowell describes Martian farms and canals.
The 19th and early 20th century American businessman and astronomer Percival Lowell popularised the idea that a race of canal-building beings lived on Mars. He observed Mars through telescopes and mapped the planet in detail. Historians and astronomers now believe Lowell mistook faint surface features for canals or imagined he saw them.
Sir Patrick Moore has doubts about Lowell's powers of observation.
Sir Patrick Moore describes how Percival Lowell mapped Mercury. Though he recognises that Lowell made many contributions to astronomy, Sir Patrick notes that his maps of other planets were not accurate.
A wealthy Bostonian is intrigued by talk of canals on the Red Planet.
The American astronomer Percival Lowell popularised the idea that an advanced civilisation built canals on Mars, and he drew elaborate maps of their irrigation network. Many astronomers at the time were sceptical. It is now thought that surface features were mistaken for canals by well intentioned pioneers.
Percival Lawrence Lowell (//; March 13, 1855 – November 12, 1916) was an American businessman, author, mathematician, and astronomer who fueled speculation that there were canals on Mars. He founded the Lowell Observatory in Flagstaff, Arizona and formed the beginning of the effort that led to the discovery of Pluto 14 years after his death.