General information about Mars

Fourth largest planet from the Sun. Because of its color, visible to the naked eye, often called the Red Planet. Mars - one of the terrestrial planets, with a diameter (6,788 km) is slightly more than half the diameter of Earth. Mars moves around the sun in an elliptical orbit with an average distance from the Sun 228,000,000 km, orbital period of 687 days, the period of rotation around the axis 24 h 37 min 22.58 s (G - Martian "day"). Orbital plane is inclined to the ecliptic plane at a slight angle (1 ° 51 '). The minimum distance from the Sun about 207, maximum - 249 million km due to this difference, the amount of solar energy varies by 20-30%. Since the inclination of the equator to the orbital plane is significant (25,2 °), on the planet there are marked seasonal changes (changing of the seasons, as on Earth). Moreover, to examine this device "Mars Global Surveyor" Image northern polar cap, it appeared that the planetary axis of Mars undergoes periodic oscillations and orbit it, too, from time to time shifts that, as on Earth, may lead to the Martian Ice Age . Its thickness, according to astronomers, is 2,5 km. In these images clearly shows the spiral structure of ice and dust ridges formed under the influence of strong winds and sunshine. shzmereniya laser altimeter indicates that this structure is typical for the whole polar cap. Scientists estimate that the age of this cap is "only" five million years. Chemin happened at the last shift on orbit, because of which began last glacial period. On Earth there are similar things, but to a lesser extent, since the stabilizing effect of the moon has a gravitational field. Mars has also a "stabilizer" is missing, so its axis may deviate from its normal position as much as 47 degrees.

Scenes from the orbital unit of Viking, passed in 1976 have been processed so that the result is a clear image of the southern hemisphere from the polar cap. Long-term study of the south pole of Mars interplanetary station "Mars Global Surveyor", in particular, will allow specialists to come to the conclusion that Mars, like Earth, periodically experienced global climate change is akin to ice ages in the history of our planet. It is noticeable that over the past two years the polar cap of Mars was much thinner, and it is not seasonality, and a more global process going for a long time. According to scientists, after a few decades, the southern polar cap of Mars may disappear entirely.
Mars obtained by CT Hubble on Feb. 25, 1995, show the entire surface of the planet at a distance of 103 million km. In 1995, Mars was more cloud than in previous years. Details are visible in the size of 50 km. Tharsis region on the image to the right of the center shows a semi-circular cloud, located above Mount Olympus. On the central image at the bottom left you can see the valley of the Mariner. On the right image to the left of the center lies a plateau Big Sirte. Closer to the east (right side) - a cloud over the volcano in the Elysium region.

The scheme of oppositions of Mars Mars is at a minimum distance from the Earth during the confrontations that occur at intervals of 779.94 Earth days. However, once in 15-17 years is the so-called grand opposition, when the two planets closer to a distance of 56 - 60 million km, the most recent such convergence took place on September 18 1988. Typically, extreme convergence happens once in 80 years. And on Aug. 27, 2003 at 09:51 UTC (13:51 vcr) an event that happens once every 6000 years - Mars closer to Earth at a distance of 55.7 million kilometers (more precisely at the moment of closest approach of the two planets are separated by "any then "55,757,930 miles).
The great confrontation usually observed between July 5 and October 5. During the great conflict Mars looks like the brightest star in the midnight sky (magnitude -2.9), orange-red color, so that it became regarded as an attribute of the god of war (hence the name of the planet).

Composition and internal structure

The chemical composition of Mars is typical for the terrestrial planets, although, of course, there are specific differences. It also occurred early redistribution of the substance under the influence of gravity, as indicated by the surviving traces of the primary magmatic activity (there is now a weak magnetic field whose strength is about 2% of Earth's field with opposite polarity of the earth and the coincidence of the northern pole. Shz of rock magnetization in some areas of local magnetic fields above ground field).

Apparently, having a relatively low temperature (1300 K) and low density, the core of Mars is rich in iron and sulfur (ie liquid, which is confirmed by data collected over three years space probe "Mars Global Surveyor", and electrical conductivity) and small in size (the radius of the order of 800-1000 km), and weight - about one tenth of the entire mass of the planet. Formation of the core, according to current theoretical estimates, lasted about a billion years, and coincided with the period of early volcanism. More of the same length of time taken by partial melting of mantle silicates, accompanied by intense volcanic and tectonic phenomena. About 3 billion years ago and ended this period, and though still at least a billion years of continued global tectonic processes (in particular, there were huge volcanoes) had already begun a gradual cooling of the planet, continues to this day. Mars registered marsotryaseniya.

Mantle of Mars is enriched with iron sulfide, a notable number of which are found in the study of surface rocks, whereas the content of metallic iron is much smaller than the other terrestrial planets. The thickness of the lithosphere of Mars - a few hundred kilometers, including about 100 km of the crust.

The bark is rich in olivine and ferruginous oxides that give the planet a rusty color. The chemical composition of the surface layer: silicon 21%, iron 12.7%, sulfur 3.1%.


Mars at a distance of 31000 km. Viking-1, made 15 black-and-white photographs on June 22 after three color filters - violet, green and red, from which was drawn colored mosaic of so-called "Grand Canyon of Mars." In the picture the equator passes through the upper left corner. North is at top left. Visible in the image area has a size of approximately 1800 x 2000 km.

The first color photograph of the Martian surface, obtained by the Viking-1 "after his landing in the plains Hrisa July 20, 1976

Equatorial radius of the planet is 3,394 miles, Polar - 3376.4 km. Level surface in the southern hemisphere on average 3-4 km higher than in the north. Portions of the surface of Mars, covered with craters, like lunar continent. If you mentally divide the planet in half a great circle tilted by 35 ° to the equator, between the two halves of Mars there is a noticeable difference in the nature of the surface. The southern part is mainly an ancient surface, much pitted with craters. In this hemisphere, are the main shock depression - plains of Hellas, and Argir shsidy. To the north is dominated by younger and less wealthy cratered surface. A significant portion of the surface of Mars is a more light areas (continents), which have a reddish-orange color, and 25% of the surface - a dark "sea" of gray-green, which level is lower than the "mainland". Elevation changes are very significant and are in the equatorial region of about 14-16 km, but there are tops that rise much higher. The highest region - large Tharsis volcanic dome mountains and plains of Elysium. Over both regions is dominated by several huge extinct volcanoes, the largest of which is Arsiya (27 km) and Olympus (26 km) in the elevated area Tarais in the northern hemisphere. This is the highest volcano in the solar system - panel. To compare the shield volcanoes of Hawaii on Earth rise above the sea floor only 9 km. Shield volcanoes grow in height gradually, as a result of repeated eruptions from the same vents. Although at the present time, these volcanoes, apparently, are no longer valid, they are likely to have formed earlier and were active for much longer than any volcano on Earth. In this hot volcanic point on the Earth over time changed their position due to the gradual movement of continental plates, so that the "building" a very high volcano in each case the time is not enough. In addition, low-gravity allows erupted substances to form on Mars is much higher structures that do not descend under its own weight.

Photographs taken from orbit block of Viking early summer morning, seen the fog and convective clouds surrounding the volcano Olympus.

In the foreground on the left - photographed by Mariner 9, lava flows on the slopes of the volcano Olympus. This area is highlighted on a map on the right square.

Observations from the satellites of Mars reveal distinct traces of volcanic and tectonic activity - faults, canyons with branching canyons, some of them have hundreds of kilometers long, tens - wide and several kilometers in depth. These volcanic areas are located on the east and west ends of the vast system of canyons - Mariner Valley, which stretches over 5000 km along the equatorial region and a width of up to 120 km has an average depth of 4-5 km. It is believed that it arose as a result of the fault associated with the thrust of the dome Tharsis. Impact craters on Mars are smaller than the Moon and Mercury, but deeper than that on Venus. However, volcanic craters reach huge sizes. The biggest of them - Arsiya, Akreus, Pavonis, and Olympus - reach 500-600 km at the bottom. The diameter of the crater at Arsii - 100, while Olympus - 60 km (for comparison - in the greatest on earth volcano Mauna Loa in Hawaii, the diameter of the crater 6.5 km). shssledovateli concluded that volcanoes were still active relatively recently, namely: a few hundred million years ago.



Straight Martian riverbed in the Land of the Sirens, received "Mariner 9".



Part of the canyon in the Valley Marineris (photo from the orbital unit of Viking-1. "Huge rift valley extends for more than 5000 km in the equatorial region of Mars.

shmeyutsya Certificate (surviving channel flows - the long branching system of valleys stretching for hundreds of miles, very similar to terrestrial rivers dried up riverbed, and the differences in elevation corresponds to the direction of the flows), which on the surface of Mars at one time there was liquid water. It seems that those channels coming from the Mariner Valley, emerged in the course of a flash flood. In addition, in heavily pitted with craters areas found traces of dried meandering rivers with many tributaries. Some features of the terrain is clearly reminiscent ironed glacier areas. Judging by the good preservation of these forms had no time nor destroyed, nor covered with successive layers, they have a relatively recent origin (within the last billion years). Brian Hynek and Roger Phillips, scientists from the University of Washington, claim that the Earth Arabia, one of the regions of Mars, located kilometers below the surrounding plateau and is comparable in size to the Earth Europe (after the measurements made by "Mars Global Surveyor"), traces the impact of water, which was about 10 million years ago.
Where is now Martian water? There is every reason to believe that a lot of water on Mars. It has been suggested that water exists today in the form of permafrost. At very low temperatures on the Martian surface (average of approx. 220 By the mid-latitudes and lish150 K in the polar regions) on any open surface water rapidly formed a thick crust of ice, which, moreover, in a short time recorded by dust and sand. In summer, temperatures at the equator slightly above 0 ° C, and most of the surface average - 23 ° C. It is not excluded that due to the low thermal conductivity of ice under its thickness in some places may stay and liquid water and, in particular, subglacial water flows continue to deepen the channel and now some of the rivers.





In the photograph obtained by the Viking-1 "in place of his landing in the plains Hrisa, see sand dunes and jagged boulders, and beneath the dunes in April 2001 in Amazonia during the dust storm and after (photo by" Mars Global Surveyor ").

Icy areas around the North Pole of Mars typical mid-summer when the seasonal polar cap of carbon dioxide offers under its water ice and soil. For the three black-and-white photo taken with the orbital unit of the Viking-2 "with 2200km through the red, green and blue filters to obtain the image of the surface area measuring approximately 60 x 30 km. The border between the ice and the planet's surface at the top of the image represents a break up to 500 m. Its steps have a height of 50 m. The regularity of the layers suggests that their relationship with the periodic changes of the orbit of Mars. It is possible that changes in Mars orbit affect the frequency and strength of global dust storms, and, consequently, the amount of matter that forms sedimentary layers of the planet. A variety of arch forms indicates the complexity of erosion processes in the northern polar region. Here, as elsewhere around the northern polar cap, there dyunopodobnye education, in addition, often dark areas with an irregular structure. Rocks, forming dunes could be formed from eroded soil layers, but no clear difference in the brightness observed between the individual layers of the dunes. Ice, the maximum thickness of which is unknown, sometimes with a thin layer covering breakage. Something where the rocks on the slope is lighter due to the coating of frost. Observations of the last few years showed that the polar ice caps decrease, which may lead in general to their disappearance in the future.

Telescopic studies of Mars have found features such as seasonal changes in its surface. This primarily refers to "white polar caps, which with the onset of autumn begin to increase (in the corresponding hemisphere), and spring pretty much" melt ", and the poles are distributed" wave warming. " It has been suggested that these waves are associated with the spread of vegetation on the surface of Mars, but more recent data have forced to abandon this hypothesis, since they are associated with transferring of sand and dust. Southern hemisphere of Mars noticeably drier than the north.
Explanation is quite simple: it turns out, the south pole almost 6,5 km above the northern and such a relief alters the atmospheric circulation in this part of the planet. Every summer is melting the polar caps of Mars. Moist carbon dioxide, from which mainly consists of the Martian atmosphere, with the south pole as the hills rolling down to the equator, and from there heading towards the North Pole, and there is added to the water vapor and carbon dioxide, which is above the northern polar cap. The result is that the polar cap at the North Pole in size much more than the south. This picture was obtained by computer simulation of atmospheric flows on Mars, taking into account the higher position the south pole. If, however, the proposed model, substitute the same height for the poles, the climate in both hemispheres receive the same.

Now Mars is waterless and lifeless desert, over which the raging storm, towering sand and dust to a height of tens of kilometers. During these storms the wind speed reaches hundreds of meters per second. However, recent studies of Mars spacecraft "Mars Global Surveyor" and "Mars Odyssey" (started work in orbit around Mars in October 2001) argue that under the surface layer at depths greater than 5m is a lot of ice, and possibly in a liquid state. If it melted, then according to experts, this water would cover Mars 500 meter layer.

Apparently, the scientists were able to first detect the fluxes of matter in the canyons on Mars. Geologist at the University of Melbourne (Australia), Dr Nick Hoffman (Nick Hoffman) on images of the Martian surface, obtained automatic station Mars Global Surveyor, have found signs of active processes in the canyons and channels in the circumpolar regions of the planet. However, despite the majority view of scientists who believe that we are talking about the flow of liquid water, Dr. Hoffman believes that it most likely frozen carbon dioxide. If he is right, attempts by NASA to detect water in liquid form, and life on Mars would be doomed to failure.
In January 2003, Dr. Hoffman presented his evidence that Mars is not lifeless. In analyzing the data obtained by automatic stations, it was discovered that the Martian spring, rushing streams in the canyons. Apparently, the "flow" is a landslide or an avalanche of "boiling" dry ice, carrying with them sand, dust and stones (and maybe this is a very salty water?).

"This finding may dispel any illusions about the existence of life on Mars - believes Mr. Hoffman. - If the mechanism of formation of all young canyons on Mars is the same, then life in the surface layers of the planet that so desperately wanted by NASA does not exist. Without Water liquid state of life can not be, but, despite numerous recent reports of the discovery on Mars more and more water ice, NASA, and found no water in its liquid state. "

Canyons on Mars are considered the most likely candidates for detection of flow of liquid water on Mars today, and many experts have focused on NASA's search for mechanisms that could explain their formation under the action of water erosion. However, before anyone could not see the canyon "in action".
Some of the large surface area of Mars
Mount Olympus (Olympus Mons) - the highest peak on Mars and the largest volcano solar system. Rises to 27 km above the reference level (defined by measurements of atmospheric pressure). This giant shield volcano, which has a diameter of about 700 km, similar to volcanoes on Earth, but its volume is at least fifty times greater than Earth's closest equivalent. The caldera has a diameter of about 90 km, and is surrounded by mountain slope height of at least 4 km. Older volcanic rocks, smoothed and destroyed by the wind, surrounded by the main peak, forming a region of Oreana. Mount Olympus is located in north-western part of the Tharsis and previously known as the Olympic snow "because the clouds, constantly swirling over this area for terrestrial observers, looked like a bright spot.

Plateau of the Sun (Solis Planum) - An ancient volcanic plains on Mars, which lies south of the Mariner Valley. By visual observation in this area shows the changing dark spots ("lake"), making the whole structure was popularly called "The Martian Eyes."

Plain Amazonia (Amazonis Planitia) - faintly plain in the northern equatorial region of Mars. Pretty young age rocks are 10-100 million years. Some of these rocks represent a stark volcanic lava. As such volcanoes in the mountains with craters in the center is not here, and lava poured from cracks Martian crust. It is particularly interesting that there were found traces of extensive lava spills that have occurred repeatedly, and lava flowed on the same system of ducts that water (or ice). Based on studies of these multilayer structures formed as a result of repeated eruptions, we may conclude that, quite possibly, volcanic processes are on Mars now, and relatively soon (a few tens of millions of years) on the surface of Mars may once again begin to flow lava.

Earth Arabia - after the measurements carried out "Mars Global Surveyor", it became known that she is kilometers below the surrounding plains. Scientists believe that this indicates that the region was subjected to erosion. Erosion could be caused by different factors: volcanic activity, glaciers, wind. However, according to scientists, the huge size of the area subjected to its effects, indicate that the erosion on Earth Arabia was caused by flowing water. Confirmation of this will probably be received in three years. Very likely that the Earth Arabia will become one of the points, which in 2004 will land unit "Mars Rover".

Plain Argir (Argyre Planitia) - Round shock depression (900 km in diameter), located in the southern hemisphere of Mars.

Plain Arcadia (Arcadia Planitia) - Plain in the northern hemisphere of Mars.

Plain Utopia (Utopia Planitia) - a vast plain with a small number of craters in the northern hemisphere of Mars. AMC landing of the Viking-2. Panoramic images transmitted to Earth Landing Module Viking, showed a surface strewn with numerous boulders, built of textured rocks.

Plain Hrisa (Chryse Planitia) - Round Plateau, will almost certainly impact basin in the northern equatorial region of Mars. Landing probe Viking 1.

Plain Elysium (Elysium Planitia) - Large volcanic plain of more than 5000 km across.

Plain Hellas (Hellas Planitia) - Impact depression nearly circular shape with a diameter of 1800 km on the surface of Mars. Plain Hellas, released a light color, has long been marked on maps of Mars. Previously it was called simply "Hellas".

Three photos of "Face on Mars": Viking-1 (1976); Mars Global Surveyor (1998) and Mars Global Surveyor (April 2001).


Rarefied Martian atmosphere contains 95.3% carbon dioxide, 2.7% of molecular nitrogen and 1.6% argon, CO (0.06%), H2O (up 0.1% and varies significantly depending on the season). Oxygen is present only in trace amounts. The atmospheric pressure at the surface is 0,7% (5-7 hPa) pressure at the surface of the Earth. However, strong atmospheric winds cause extensive dust storms that sometimes cover the entire planet, kicking up dust to a height of 20km.
On Mars, there are different forms of clouds and fog. Early morning fog thickens in the valleys and on as winds pick up the cooling air mass in the high plateau, the clouds appear over the high mountains of Tharsis. In winter, the northern polar cap is shrouded veil of ice fog and dust, called the polar hood. A similar phenomenon to a lesser extent is also observed in the south.
The polar regions are covered with a thin layer of ice that is believed to be a mixture of water ice and solid carbon dioxide. shzobrazheniya high resolution show the spiral formation and the strata caused by the wind material. North polar region is surrounded by rows of sand dunes. Polar ice caps grow and decay in accordance with the seasons. Martian year, roughly twice as long as the earth, so that the seasons are also longer. However, due to the relatively high eccentricity of the orbit of Mars, they have an unequal length: summer in the Southern Hemisphere (which occurs when Mars is near perihelion) are shorter and hotter summers in the north.

shmeetsya weak ozone layer at an altitude of 36-40km thick and 7 km to 250 times weaker terrestrial.

Pink cloud formations moving over the surface of Mars from the northeast at a speed of 6.7 m / sec at an altitude of 16 km. Clouds consist of frozen water that condenses on reddish dust particles floating in the planet's atmosphere. The photo was taken with Pesfayndera "for about 40 minutes before sunrise.


Mars has two tiny natural satellites - Phobos and Deimos, which are close to the planet on nearly circular orbits lying in the equatorial plane. See them from Earth is very difficult. They are so different from Mars, which is likely to represent a captured asteroid.

If researchers NASA (a group of scientists led by David Mc Kay) are right, this meteorite weighing 1.9 kg contains evidence that Mars billions of years ago there was a primitive (bacterial) life. Meteorite ALH 84001, found in Antarctica in 1984, is believed to have formed from the Martian rocks total about 16 million years ago, when hitting the surface of Mars, a large meteor body. In the matter of meteorites found organic compounds that are similar to products of vital activity of terrestrial bacteria. Ibid discovered mineral formations corresponding to side products of bacterial activity, and small balls of carbonates, which can be mikroiskopaemymi simple bacteria.


This image was made at the end of the day. The rover "Sojourner" is on top of the dunes Mermeyd, dark color that is different from the light surrounding surface. Dark red tracks are drawn from the first plan to the wheels of the rover.

Mars has long been considered as the only (besides Earth) planet, which is probably the existence of life, reinforced by the observation that the polar ice caps, and seasonal changes. Hope people find "brothers on reason" revived with new vigor after A. Secchi in 1859 and, especially, D. Skiparelli in 1877 launched a sensational hypothesis that Mars is covered with a network of man-made channels that periodically fill with water. Percival Lowell and others have convinced themselves that they see a system of direct channels - channels that could have an artificial origin. shssledovanie planet automatic interplanetary stations actually put an end to conjectures about the possible existence in the present life on Mars. However, the study of meteorites, which have, apparently, Martian origin, once again led to speculation that at least in the distant past when the climate was more humid and warm, on Mars could be microscopic life. shssledovannye meteorites have shown that a quarter of their magnetic substances produced by bacteria. Some of the minerals found in meteorites are signs of long-term interaction with water, which may serve as indirect confirmation that once existed on Mars oceans. The surface of Mars is covered with black stones dross, but inside they are dark green. Age of meteorites, scientists believe, at least 8.7 million years.
The largest of the scientists found meteorites of Martian origin weighs about 18 kg. It was discovered in 1962 in Nigeria.

In addition, in 2001, associate professor of neurobiology Faculty of Medicine, University of Southern California, Joseph Miller (Joseph Miller) again reviewed the data collected by Viking and concluded that life existed on Mars in the report on the results of their research at the Annual Conference of the International Society Optical Engineers (International Society for Optical Engineering), he reported that in soil samples showed traces of nutrients recycled by some living organisms. And, according to him, such substances can only be found in living cells. 25 years ago, the "hand" robot-manipulator probe "Viking" taken from the surface soil samples and p