46 Facts About Mars


Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, being larger than only Mercury.

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Mars is a terrestrial planet with a thin atmosphere, and has a crust primarily composed of elements similar to Earth's crust, as well as a core made of iron and nickel.

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Mars has surface features such as impact craters, valleys, dunes, and polar ice caps.

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Some of the most notable surface features on Mars include Olympus Mons, the largest volcano and highest known mountain on any planet in the Solar System, and Valles Marineris, one of the largest canyons in the Solar System.

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Days and seasons on Mars are comparable to those of Earth, as the planets have a similar rotation period and tilt of the rotational axis relative to the ecliptic plane.

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Mars has been explored by several uncrewed spacecraft, beginning with Mariner 4 in 1965.

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Two countries have successfully deployed rovers on Mars, the United States first doing so with Sojourner in 1997 and China with Zhurong in 2021.

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Mars can be viewed from Earth with the naked eye, as can its reddish coloring.

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In Mesopotamian texts, Mars is referred to as the "star of judgement of the fate of the dead.

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For Mars, they knew that the planet made 37 synodic periods, or 42 circuits of the zodiac, every 79 years.

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Literature from ancient China confirms that Mars was known by Chinese astronomers by no later than the fourth century BCE.

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From Brahe's observations of Mars, Kepler deduced that the planet orbited the Sun not in a circle, but in an ellipse.

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In 1610, Mars was viewed by Italian astronomer Galileo Galilei, who was first to see it via telescope.

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The first person to draw a map of Mars that displayed any terrain features was the Dutch astronomer Christiaan Huygens.

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Mars published several books on Mars and life on the planet, which had a great influence on the public.

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Seasonal changes in combination with the canals led to speculation about life on Mars, and it was a long-held belief that Mars contained vast seas and vegetation.

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Mars is approximately half the diameter of Earth, with a surface area only slightly less than the total area of Earth's dry land.

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Core of Mars is overlain by the rocky mantle, which, however, does not seem to have a layer analogous to the Earth's lower mantle.

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Mars is a terrestrial planet whose surface consists of minerals containing silicon and oxygen, metals, and other elements that typically make up rock.

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Mars has many distinctive chemical features caused by its position in the Solar System.

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Geological history of Mars can be split into many periods, but the following are the three primary periods:.

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Radar data from Mars Express and the Mars Reconnaissance Orbiter show large quantities of ice at both poles, and at middle latitudes.

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Landforms visible on Mars strongly suggest that liquid water has existed on the planet's surface.

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The surface of Mars as seen from Earth is divided into two kinds of areas, with differing albedo.

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Mars's equator is defined by its rotation, but the location of its Prime Meridian was specified, as was Earth's, by choice of an arbitrary point; Madler and Beer selected a line for their first maps of Mars in 1830.

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Mars has no oceans and hence no "sea level", a zero-elevation surface had to be selected as a reference level; this is called the areoid of Mars, analogous to the terrestrial geoid.

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Mars is located closer to the asteroid belt, so it has an increased chance of being struck by materials from that source.

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Mars is more likely to be struck by short-period comets, i e, those that lie within the orbit of Jupiter.

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The highest atmospheric density on Mars is equal to that found 35 kilometres above Earth's surface.

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In September 2017, NASA reported radiation levels on the surface of the planet Mars were temporarily doubled, and were associated with an aurora 25 times brighter than any observed earlier, due to a massive, and unexpected, solar storm in the middle of the month.

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All the planets in the Solar System, the seasons of Mars are the most Earth-like, due to the similar tilts of the two planets' rotational axes.

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Mars is near perihelion when it is summer in the Southern Hemisphere and winter in the north, and near aphelion when it is winter in the Southern Hemisphere and summer in the north.

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The solar day on Mars is only slightly longer than an Earth day: 24 hours, 39 minutes, and 35.

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Mars has a relatively pronounced orbital eccentricity of about 0.

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Campbell at Lick Observatory observed the planet and found that "if water vapor or oxygen occur in the atmosphere of Mars it is in quantities too small to be detected by spectroscopes then available".

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Lack of a magnetosphere and the extremely thin atmosphere of Mars are a challenge: the planet has little heat transfer across its surface, poor insulation against bombardment of the solar wind and insufficient atmospheric pressure to retain water in a liquid form.

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Mars is nearly, or perhaps totally, geologically dead; the end of volcanic activity has apparently stopped the recycling of chemicals and minerals between the surface and interior of the planet.

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Tests conducted by the Phoenix Mars lander have shown that the soil has an alkaline pH and it contains magnesium, sodium, potassium and chloride.

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Small quantities of methane and formaldehyde detected by Mars orbiters are both claimed to be possible evidence for life, as these chemical compounds would quickly break down in the Martian atmosphere.

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Likewise, the glass in impact craters on Mars could have preserved signs of life, if life existed at the site.

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NASA's Mariner 4 was the first spacecraft to visit Mars; launched on 28 November 1964, it made its closest approach to the planet on 15 July 1965.

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The data from Mariner 9 and Viking allowed better maps of Mars to be made, and the Mars Global Surveyor mission, which launched in 1996 and operated until late 2006, produced complete, extremely detailed maps of the Martian topography, magnetic field and surface minerals.

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Several plans for a human mission to Mars have been proposed throughout the 20th and 21st centuries, but none have come to fruition.

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Mars is usually close enough for particularly good viewing once or twice at 15-year or 17-year intervals.

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Idea that Mars was populated by intelligent Martians became widespread in the late 19th century.

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High-resolution mapping of the surface of Mars revealed no artifacts of habitation, but pseudoscientific speculation about intelligent life on Mars still continues.

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