Life on Mars: Difference between revisions

[[Geology of Mars|Mars' polar ice caps]] were observed as early as the mid-17th century, and they were first proven to grow and shrink alternately, in the summer and winter of each hemisphere, by [[William Herschel]] in the latter part of the 18th century. By the mid-19th century, astronomers knew that [[Mars]] had certain other similarities to Earth, for example that the [[Timekeeping on Mars|length of a day on Mars]] was almost the same as a day on Earth. They also knew that its [[axial tilt]] was similar to Earth's, which meant it experienced seasons just as Earth does - but of nearly double the length owing to its [[Darian calendar|much longer year]]. These observations led to the increase in speculation that the darker [[albedo feature]]s were water, and brighter ones were land. It was therefore natural to suppose that Mars may be inhabited by some form of life.

 

 

Spectroscopic analysis of Mars' atmosphere began in earnest in 1894, when U.S. astronomer [[William Wallace Campbell]] showed that neither water nor oxygen were present in the Martian atmosphere.<ref name="chambers">{{Citation

Unlike the [[Mars Pathfinder]] ''Sojourner'' rover and the [[Mars Exploration Rover]]s, which used [[Airbag#Aerospace Applications|airbag-cushioned capsules]] to land on Mars, the Phoenix lander will land the same way that the Viking landers did, despite the claims that rocket exhaust may have contaminated the Viking landing sites.<ref name="viking killers">2nd</ref>

 

 

===Future missions===