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Mars Timeline of Discovery:
1800 thru 1962
By Jim Plaxco
Last Updated: December 1999
The Mars Timeline of Discovery is a work in progress.
Its goal is to give the reader a general feel for the progress in humankind's understanding
of the planet Mars.
The timeline is divided into two parts. Part 1 covers the years 1570BC thru 1799.
Part 2, this document, covers the years 1800 thru 1962.
Please note that only brief references are given herein to the various planetary missions to
Mars for the purpose of placing other advances in context. A much fuller treatment of these
missions is provided separately in the Robotic Missions area.
1809 - Yellow Clouds Observed on Mars
H. Falaugergues records observing yellow clouds on Mars.
1877 - Schiaparelli Produces Map of Mars with Canali
Giovanni Schiaparelli (1835-1910), an Italian astronomer, produces a detailed map of Mars based on his observations of the planet with an 8.5 inch refractor during a favorable conjunction. His map gave classical names to the features he observed. These feature names became widely accepted. This map is also famous for the inclusion of features Schiaparelli identified as canali, an Italian word for a naturally occuring channel.
1877 - Asaph Hall Discovers Moons of Mars
Asaph Hall (1829-1907), an American astronomer, during a favorable conjunction of Mars discovers that the planet has two moons with the 26 inch refractor at the US Naval Observatory. His initial observation was made on August 12. His first observation of the second moon occurred on August 18. Additional observations thru the 20th convinced him of his discovery.
The two moons are named for two sons of Ares, the God of War: Phobos (Greek for fear) and Deimos (Greek for terror). See Observations and Orbits of the Satellites of Mars, Asaph Hall, 1878, Washington DC.
1894 - Lowell Observatory Established to Study Mars
Percival Lowell (1855-1916), American astronomer, establishes the Lowell Observatory outside of Flagstaff, Arizona. The observatory is built in time to carry out observations of the 1894 opposition of Mars. Using 12" and 18" refractors, observations are made continuously from the end of May 1894 through April 1895 by Lowell and his assistants W.H. Pickering and A.E. Douglass.
1905 - Martian Canals Photographed
C.O. Lampland of the Lowell Observatory in Arizona takes a photograph of Mars that shows 38 canals. Lampland receives an award for the photo from the British Royal Photographic Society in 1909.
1907 - Alfred Russel Wallace says Craters formed by Meteorite Impacts
Alfred Russel Wallace (1823 - 1913), English scientist and author of the theory of Natural
Selection, proposes that the craters observed on Mars are formed by the impact of meteorites.
1912 - Chemist Arrhenius Proposes Chemical Explanation for Changing Albedo Features on Mars
Svante Arrhenius, a Swedish chemist and Nobel Laureate, proposes that the observed changes in Martian albedo features are not necessarily the result of seasonal changes in vegetation on Mars. Rather, he believes that the changes could be explained by some simple chemical reaction that is brought on by the melting of the polar ice caps.
1920's - Temperature of Mars Estimated
During the 1920's, Seth Nicholson and Edison Pettit of the Mt. Wilson Observatory, collect "radiation" from the planets using a 100" mirror. The light collected by the mirror was focused on a thermocouple which then generated an electric current. This current was then measured by a galvanometer. Their measurements of the light from Mars resulted in an estimate that the surface temperatures in the equatorial regions of Mars at noon hit 60 degrees Fahrenheit. Temperatures along the limb of Mars at sunrise were measured to be approximately -120 degrees Fahrenheit. The light coming from the polar regions was to weak for the temperatures there to be determined.
1950 - Pluto Discoverer Tombaugh Proposes New Explanation for Martian Canals
Clyde Tombaugh, a member of the Lowell Observatory and discoverer of Pluto, proposes that the canals of Mars are really fractures. Tombaugh proposes that the oasis, which are the hub for systems of radiating canals, are craters resulting from cosmic impacts. The canals that radiate from these oasis are actually fractures caused by the impact while the variations in their appearance is caused by the ebb and flow of plant life.
1953 - International Mars Committee Established
On the initiative of the Lowell Observatory, an International Mars Committee is organized to coordinate continuous observation of Mars during the favorable opposition of 1954.
1962 - Photographic History of Mars Published
Earl Charles Slipher, an astronomer at the Lowell Observatory, publishes the book Photographic History of Mars (1905-1961).
Proceed to Part 1: 1570BC thru 1799AD.
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