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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] |
Mars Earth Orbit
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of Mars surface color, its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () Atmosphere of Mars, 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, Groundwater on Mars, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and Martian polar ice caps, 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 List of Solar System objects by size, 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. Martian regolith#Atmospheric dust, Fine dust is prevalent across the surface and the atmosphere, bein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sidereal Day
Sidereal time ("sidereal" pronounced ) is a system of timekeeping used especially by astronomers. Using sidereal time and the celestial coordinate system, it is easy to locate the positions of celestial objects in the night sky. Sidereal time is a "time scale that is based on Earth's rate of rotation measured relative to the fixed stars". A sidereal day (also known as the sidereal rotation period) represents the time for one rotation about the planet axis relative to the stars. Viewed from the same location, a star seen at one position in the sky will be seen at the same position on another night at the same time of day (or night), if the day is defined as a sidereal day. This is similar to how the time kept by a sundial (Solar time) can be used to find the location of the Sun. Just as the Sun and Moon appear to rise in the east and set in the west due to the rotation of Earth, so do the stars. Both solar time and sidereal time make use of the regularity of Earth's rot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Panels
A solar panel is a device that converts sunlight into electricity by using photovoltaic (PV) cells. PV cells are made of materials that produce excited electrons when exposed to light. These electrons flow through a circuit and produce direct current (DC) electricity, which can be used to power various devices or be stored in batteries. Solar panels are also known as solar cell panels, solar electric panels, or PV modules. Solar panels are usually arranged in groups called arrays or systems. A photovoltaic system consists of one or more solar panels, an inverter that converts DC electricity to alternating current (AC) electricity, and sometimes other components such as controllers, meters, and trackers. Most panels are in solar farms or rooftop solar panels which supply the electricity grid. Some advantages of solar panels are that they use a renewable and clean source of energy, reduce greenhouse gas emissions, and lower electricity bills. Some disadvantages are tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Science Laboratory
Mars Science Laboratory (MSL) is a robotic spacecraft, robotic space probe mission to Mars launched by NASA on November 26, 2011, which successfully landed ''Curiosity (rover), Curiosity'', a Mars rover, in Gale (crater), Gale Crater on August 6, 2012. The overall objectives include investigating Mars' Planetary habitability, habitability, studying its Climate of Mars, climate and Planetary geology, geology, and collecting data for a human mission to Mars. The rover carries a variety of scientific instruments designed by an international team. Overview MSL carried out the most accurate Martian landing of any spacecraft at the time, hitting a target landing ellipse of , in the Aeolis Palus region of Gale Crater. MSL landed east and north of the center of the target. This location is near the mountain Aeolis Mons (a.k.a. "Mount Sharp"). The Mars Science Laboratory mission is part of NASA's Mars Exploration Program, a long-term effort for the robotic exploration of Mars tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phoenix (spacecraft)
''Phoenix'' was an uncrewed space probe that landed on the surface of Mars on May 25, 2008, and operated until November 2, 2008. ''Phoenix'' was operational on Mars for sols ( days). Its instruments were used to assess the local habitability and to research the history of water on Mars. The mission was part of the Mars Scout Program; its total cost was $420 million, including the cost of launch. The multi-agency program was led by the Lunar and Planetary Laboratory at the University of Arizona, with project management by NASA's Jet Propulsion Laboratory. Academic and industrial partners included universities in the United States, Canada, Switzerland, Denmark, Germany, the United Kingdom, NASA, the Canadian Space Agency, the Finnish Meteorological Institute, Lockheed Martin Space Systems, MacDonald Dettwiler & Associates (MDA) in partnership with Optech Incorporated ( Optech) and other aerospace companies. It was the first NASA mission to Mars led by a public university. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Exploration Rover
NASA's Mars Exploration Rover (MER) mission was a robotic space mission involving two Mars rovers, ''Spirit (rover), Spirit'' and ''Opportunity (rover), Opportunity'', exploring the planet Mars. It began in 2003 with the launch of the two rover (space exploration), rovers to explore the Martian surface and Geology of Mars, geology; both landed on Mars at separate locations in January 2004. Both rovers far outlived their planned missions of 90 Timekeeping on Mars#Sols, Martian solar days: MER-A ''Spirit'' was active until March 22, 2010, while MER-B ''Opportunity'' was active until June 10, 2018. Objectives The mission's scientific objective was to search for and characterize a wide range of rock (geology), rocks and soils that hold clues to past Water on Mars, water activity on Mars. The mission is part of NASA's Mars Exploration Program, which includes three previous successful landers: the two Viking program landers in 1976 and Mars Pathfinder probe in 1997. The scientific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Pathfinder
''Mars Pathfinder'' was an American robotic spacecraft that landed a base station with a rover (space exploration), roving probe on Mars in 1997. It consisted of a Lander (spacecraft), lander, renamed the Carl Sagan Memorial Station, and a lightweight, wheeled robotic Mars rover named ''Sojourner (rover), Sojourner'', the first rover to operate outside the Earth–Moon system. The mission terminated in 1998. Launched on December 4, 1996, by NASA aboard a Delta II booster a month after the ''Mars Global Surveyor'', it landed on July 4, 1997, on Mars's Ares Vallis, in a region called Chryse Planitia in the Oxia Palus quadrangle. The lander (spacecraft), lander then opened, exposing the rover which conducted many experiments on the Martian surface. The mission carried a series of scientific instruments to analyze the Martian Celestial body atmosphere, atmosphere, climate, and geology and the composition of its rock (geology), rocks and soil. It was the second project from NASA's D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terrestrial Time
Terrestrial Time (TT) is a modern astronomical time standard defined by the International Astronomical Union, primarily for time-measurements of astronomical observations made from the surface of Earth. For example, the Astronomical Almanac uses TT for its tables of positions ( ephemerides) of the Sun, Moon and planets as seen from Earth. In this role, TT continues Terrestrial Dynamical Time (TDT or TD),TT is equivalent to TDT, see IAU conference 1991, Resolution A4, recommendation IV, note 4. which succeeded ephemeris time (ET). TT shares the original purpose for which ET was designed, to be free of the irregularities in the rotation of Earth. The unit of TT is the SI second, the definition of which is based currently on the caesium atomic clock,IAU conference 1991, Resolution A4, recommendation IV, part 2 states that the unit for TT is to agree with the SI second 'on the geoid'. but TT is not itself defined by atomic clocks. It is a theoretical ideal, and real clocks can onl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Otto Lampland
Carl Otto Lampland (December 29, 1873 – December 14, 1951) was an American astronomer. He was involved with both of the Lowell Observatory solar system projects, observations of the planet Mars and the search for Planet X. Biography Carl Otto Lampland was born near Hayfield in Dodge County, Minnesota. He was born into a family of ten children. Both his father Ole Helliksen Lampland (1834–1914) and his mother Berit Gulliksdatter Skartum (1850–1943) were born in Norway. He was educated first at Valparaiso Normal School in Valparaiso, Indiana, where he earned a B.S. degree in 1899. He then studied at Indiana University Bloomington, where he received a B.A. degree in astronomy in 1902, an M.A. in 1906, and an honorary LL.D in 1930. He first went to Lowell Observatory in 1902 when invited by Percival Lowell and Lampland was closely involved with Lowell in planetary observation. He designed cameras used for astronomy and also designed and maintained telescopes, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sol (day On Mars)
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] |
Julian Date
The Julian day is a continuous count of days from the beginning of the Julian period; it is used primarily by astronomers, and in software for easily calculating elapsed days between two events (e.g., food production date and sell by date). The Julian period is a chronological interval of 7980 years, derived from three multi-year cycles: the Indiction, Solar, and Lunar cycles. The last year that was simultaneously the beginning of all three cycles was , so that is year 1 of the current Julian period, making AD year of that Period. The next Julian Period begins in the year AD 3268. Historians used the period to identify Julian calendar years within which an event occurred when no such year was given in the historical record, or when the year given by previous historians was incorrect. The Julian day number (JDN) has the same epoch as the Julian period, but counts the number of days since the epoch rather than the number of years since then. Specifically, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viking Program
The ''Viking'' program consisted of a pair of identical American space probes, ''Viking 1'' and ''Viking 2'' both launched in 1975, and landed on Mars in 1976. The mission effort began in 1968 and was managed by the NASA Langley Research Center.Soffen, G. A. (July–August 1978). "Mars and the Remarkable Viking Results." ''Journal of Spacecraft and Rockets''. 15 (4): 193-200. Each spacecraft was composed of two main parts: an orbiter spacecraft which photographed the surface of Mars from orbit, and a Lander (spacecraft), lander which studied the planet from the surface. The orbiters also served as communication relays for the landers once they touched down. The Viking program grew from NASA's earlier, even more ambitious, Voyager program (Mars), Voyager Mars program, which was not related to the successful Voyager program, Voyager deep space probes of the late 1970s. ''Viking 1'' was launched on August 20, 1975, and the second craft, ''Viking 2'', was launched on September 9, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
