Mars, canals of


Mars, canals of
Apparent systems of straight-line markings on the surface of Mars, now known to be an illusion caused by the chance alignment of large craters and other surface features.

Giovanni Virginio Schiaparelli (1835–1910) observed about 100 of what he described as channels. Percival Lowell called them canals and believed them to be evidence of intelligent life. Most astronomers could not see them, and many doubted their reality. The controversy was finally resolved only when pictures from Mariner spacecraft showed nothing resembling a network of channels.

* * *

      apparent systems of long, straight linear markings on the surface of Mars that are now known to be illusions caused by the chance alignment of craters and other natural surface features seen in telescopes near the limit of resolution. They were the subject of much controversy in the late 19th and early 20th centuries and influenced popular thinking about the possibility of life beyond Earth.

      The Italian astronomer and statesman Giovanni Virginio Schiaparelli (Schiaparelli, Giovanni Virginio) reported observing about 100 of these markings, beginning in 1877, and described them as canali (Italian: “channels”), a neutral term that implied nothing about their origin. Other observers had earlier noted similar markings, but Schiaparelli's writings first drew wide attention to the subject. About the turn of the 20th century the American astronomer Percival Lowell (Lowell, Percival) became the champion of those who believed the markings to be bands of vegetation, kilometres wide, bordering irrigation ditches, or canals, dug by intelligent beings to carry water from the polar caps. Lowell and others described canal networks studded with dark intersections called oases and covering much of the surface of the planet. Occasionally the lines were perceived as doubled; i.e., two parallel lines became visible where only a single canal had been seen before.

      Most astronomers could see no canals, and many doubted their reality. Experiments with untrained observers showed that disconnected features in diagrams or drawings might be perceived as straight-line networks when viewed at the proper distance. Telescopic photography through Earth's atmosphere offered no solution, because the lines were barely discernible by the human eye and beyond the recording capability of the camera. The controversy was finally resolved only when close-up images of the Martian surface were taken from spacecraft, beginning with Mariner 4 (1965) and Mariners 6 and 7 (1969). These showed many craters and other features but nothing resembling networks of long linear channels, either natural or artificial.

* * *


Universalium. 2010.

Look at other dictionaries:

  • Mars — /mahrz/, n. 1. the ancient Roman god of war and agriculture, identified with the Greek god Ares. 2. Astron. the planet fourth in order from the sun, having a diameter of 4222 miles (6794 km), a mean distance from the sun of 141.6 million miles… …   Universalium

  • Canals (France) — Canals (Tarn et Garonne) Pour les articles homonymes, voir Canals. Canals …   Wikipédia en Français

  • Mars Society — Founded August, 1998 Key people Board of Directors: Robert Zubrin (chairman) Scott Horowitz James Heiser Declan O Donnell Officers and Staff: Lucinda Land (Executive Director) Heat …   Wikipedia

  • Mars Direct — is a proposal for a manned mission to Mars. Proponents of the scheme have claimed it to be both cost effective and that it can be conducted with current technology. It was originally detailed in a research paper by NASA engineers Robert Zubrin… …   Wikipedia

  • Mars in the fiction of Leigh Brackett — The planet Mars appears frequently as a setting for many of the stories of Leigh Brackett, and Mars and Martians are frequently mentioned in other stories of the Leigh Brackett Solar System. Brackett s Mars shares some characteristics with the… …   Wikipedia

  • Mars in fiction — Fictional representations of Mars have been popular for over a century. Interest in Mars has been stimulated by the planet s dramatic red color, by early scientific speculations that its surface conditions might be capable of supporting life, and …   Wikipedia

  • Mars — This article is about the planet. For other uses, see Mars (disambiguation) …   Wikipedia

  • Canals (Tarn-et-Garonne) — Pour les articles homonymes, voir Canals. 43° 51′ 09″ N 1° 17′ 34″ E …   Wikipédia en Français

  • Mars landing — View from the NASA Phoenix lander in 2008 A Mars landing is a landing of a spacecraft on the surface of Mars. Of multiple attempted Mars landings by robotic, unmanned spacecraft, six were successful. There have also been studies for a possible… …   Wikipedia

  • Mars to Stay — Concept for NASA Design Reference Mission Architecture 5.0 (2009) Mars to Stay missions propose astronauts sent to Mars for the first time should stay there indefinitely, both to reduce cost and to ensure permanent settlement of Mars. Among many… …   Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.