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Mars Year 1
Mars Year 1 is the first year of Martian timekeeping standard developed by Clancy et al. originally for the purposes of working with the cyclical temporal variations of meteorological phenomena of Mars, but later used for general timekeeping on Mars. Mars Years have no officially adopted month systems. Scientists generally use two sub-units of the Mars Year: * the Solar longitude (Ls) system: 360 degrees per Mars Year that represent the position of Mars in its orbit around the Sun, or * the Sol system: 668 sols per Mars Year. This system consists of uniform time units. However, Mars Year sols may be confused with rover mission times that are also expressed in sols. Unlike in the day vs. sol distinction, "Mars Year" has no unique Latin term. Start and End dates of Mars Years were determined for 1607–2141 by Piqueux et al. Earth and Mars dates can be converted in the Mars Climate Database, however, the Mars Years are only rational to apply to events that take place on Mars. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timekeeping On Mars
Though no standard exists, numerous calendars and other timekeeping approaches have been proposed for the planet Mars. The most commonly seen in the scientific literature denotes the time of year as the number of degrees on its orbit from the northward equinox, and increasingly there is use of numbering the Martian years beginning at the equinox that occurred April 11, 1955.). Mars has an axial tilt and a rotation period similar to those of Earth. Thus, it experiences seasons of spring, summer, autumn and winter much like Earth. Mars's orbital eccentricity is considerably larger, which causes its seasons to vary significantly in length. A sol, or Martian day, is not that different from an Earth day: less than an hour longer. However, a Mars year is almost twice as long as an Earth year. Sols The average length of a Martian sidereal day is (88,642.663 seconds based on SI units), and the length of its solar day is (88,775.244 seconds). The corresponding values for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Longitude
Solar longitude, commonly abbreviated as Ls (pronounced ''ell sub ess''), is the longitude of the Sun as seen from a given body, i.e. the position of the Sun on the celestial sphere along the orbital plane of that body. It is also an effective measure of the position of the Earth (or any other Sun-orbiting body) in its orbit around the Sun, usually taken as zero at the moment of the vernal equinox. Since it is based on how far the Earth has moved in its orbit since the equinox, it is a measure of what time of the tropical year (the year of seasons) the planet is in, but without the inaccuracies of a calendar date, which is perturbed by leap years and calendar imperfections. Its independence from a calendar also allows it to be used to tell the time of year on other planets, such as Mars. Solar longitude does not increase linearly with time, the deviation being larger the greater the eccentricity of the orbit. For instance, here are the dates for multiples of 90° solar longitude on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Sol
Sol (borrowed from the Latin word for sun) is a solar day on Mars; that is, a Mars-day. A sol is the apparent interval between two successive returns of the Sun to the same meridian (sundial time) as seen by an observer on Mars. It is one of several units for timekeeping on Mars. A sol is slightly longer than an Earth day. It is approximately 24 hours, 39 minutes, 35 seconds long. A Timekeeping on Mars#Martian year, Martian year is approximately 668.6 sols, equivalent to approximately 687 Earth days or 1.88 Earth years. The sol was adopted in 1976 during the Viking program, Viking Lander missions and is a unit of measurement, measure of time mainly used by NASA when, for example, scheduling the use of a Mars rover. Length The average duration of the day-night cycle on Mars—i.e., a Martian day—is 24 hours, 39 minutes and 35.244 seconds, equivalent to 1.02749125 Earth days. The sidereal rotational period of Mars—its rotation compared to the fixed stars—is 24 hours, 37 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Climate Database
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmospheric pressure is a few thousandths of Earth's, atmospheric temperature ranges from and cosmic radiation is high. Mars retains some water, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and ice caps (with seasonal snow), but no liquid surface water. Its surface gravity is roughly a third of Earth's or double that of the Moon. It is half as wide as Earth or twice the Moon, with a diameter of , and has a surface area the size of all the dry land of Earth. Fine dust is prevalent across the surface and the atmosphere, being picked up and spread at the low Martian gravity even by the weak wind of the tenuous atmosphere. The terrain of Mars roughly follows a north-south divid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
