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Combining these various factors together into a coherent picture, you can see that the southern hemisphere is a place of more extreme variation, whereas the northern hemisphere is a place of relative moderation. Southern winters are longer and colder, and southern summers are shorter and hotter. |
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The southern hemisphere seems to contain the bulk of the more interesting areological features, so future inhabitants of Mars may have to choose between scientifically significant landscape and temperature extremes in their decisions for siting their settlements. The Hellas Basin area, being the lowest point on the Martian surface, has a greater air pressure than any other place and might be one logical location for a first colony. |
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The term areological is an invented one, which replaces the stem geos, literally meaning Earth in Greek, with a prefix derived from Aries, or Mars. The term thus means "pertaining to the study of Mars", and particularly to Martian geology, which is to say, areology. |
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9.13.2.1
Structural Details |
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When constructing a calendar for the planet Earth, we rely on certain magic numbers, such as the length of the tropical year, which are so well known that we often forget their meaning. When considering a calendar for another planet, one must start from scratch and derive these fundamental numbers. |
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This calendar for the planet Mars is based on the following data and calculations, which are mostly derived from The Book of Mars by Glasstone: |
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The length of the Martian sidereal day is 24 hours 37 minutes 22.56 seconds in terms of Terran time. |
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The length of the Martian year, considered as its sidereal period, is 686.98 Terran days. |
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9.13.2.1.2
Martian Mean Solar Day |
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With this data, you may proceed to calculate the length of the Martian mean solar day in the following way. |
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First, you know that there are 360 degrees in a circle, so you can calculate the average number of degrees per Martian day spent in orbit around the Sun as: |
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