Mars is basically a desert planet, its surface is covered with sand dunes and gravel, and there is no stable liquid water body (20 15 On September 28th, NASA announced that there is a small amount of water on Mars). The atmosphere dominated by carbon dioxide is thin and cold, and dust is suspended in it, and dust storms often occur every year. The polar caps composed of water ice and dry ice at the poles of Mars will fluctuate with the seasons.
Compared with the earth, the geological activities of Mars are relatively inactive. Most of the surface landforms were formed in ancient times, with dense craters, volcanoes and canyons, including Mount Olympus, the highest peak in the solar system, and Mariner Canyon, the largest canyon. Another topographical feature is the obvious difference between the northern and southern hemispheres: the southern part is an ancient highland covered with craters, while the northern part is a younger plain.
Mars has two natural satellites: Phobos and Phobos, which are irregular in shape and may be isolated dwarf planets. On earth, Mars is visible to the naked eye, with the highest brightness reaching -2.9. Among the eight planets, it is darker than Jupiter and Venus. On September 28th, 20 15, NASA announced the existence of running water on Mars.
The most spectacular feature on Mars is the Grand Canyon in the southern hemisphere, especially? Mariner's Valley? More prominent. Mariner's Valley consists of a series of canyons, stretching over 5,000 kilometers, 500 kilometers wide and about 6,000 meters deep. Such a canyon is incomparable to any canyon on the earth. Olympus shield volcano is even more magical. This crater with a diameter of 600 kilometers is 26 kilometers higher than the surrounding area, which is more than three times that of Mount Everest on earth. Extraordinary landforms like Mariner's Valley and Mount Olympus are unique in the whole solar system.
Mars is a cold and barren planet with a diameter of 6787 kilometers. On the surface of Mars, which is covered with rubble and desolate and silent, there are many craters formed by the impact of meteorites.
The surface of Mars is very desolate, and the bright orange area seen from the telescope belongs to it? Mainland? There are yellow and red sand dunes and strange rocks everywhere. There are obvious differences between the northern and southern hemispheres of Mars. The northern hemisphere is relatively flat, with occasional extinct volcanoes, which is 4 kilometers lower than the southern hemisphere on average, while the southern hemisphere has more craters, large and small, with gentle slopes and ridges. Weathering? Function. In terms of scale, craters on Mars not only originated from meteorites, but also resulted from volcanic activities. 100 years ago? Mars canal? In fact, it is the illusion caused by these craters and their shadows.
Is there anything strange on Mars? River bed? These dry river beds are criss-crossed, and it seems that the main stream and tributaries are connected, as many as thousands. Most people think that it is caused by the huge lava ejected by the volcano in the early active era of Mars, but some people think that it may not be ruled out that this may be a real river relic. Although there is no liquid water on Mars at present, there may be a period of high temperature in the early stage of the formation of Mars, and it is entirely possible to form a large amount of liquid water, thus producing real rivers and huge rivers.
Mars is red. The red hue of Mars is mainly caused by the distribution of various reddish-brown minerals containing Fe(III) oxides or hydroxyl oxides on its surface. Previous studies have shown that hematite is the most stable Fe(III) oxide mineral, and dissolved Fe(II) can form metastable Fe(III) oxides and hydroxyl oxide precursors under the action of O2, UV or hydrogen peroxide. In addition, mitra, a professor at the University of Washington, St. Louis, found through research that there is a new oxidation pathway under the conditions of Mars, namely chlorate (ClO3? ) can oxidize dissolved Fe(II) and produce Fe(III)-containing minerals.