Temperatures on Mars are a cold mystery. Temperature of the red planet Temperature of Mars in degrees
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The planet Mars has an equatorial diameter of 6787 km, i.e. 0.53 of Earth's. The polar diameter is slightly smaller than the equatorial diameter (6753 km) due to polar compression equal to 1/191 (versus 1/298 for the Earth). Mars rotates around its axis in almost the same way as the Earth: its rotation period is 24 hours. 37 min. 23 seconds, which is only 41 minutes. 19 sec. more period rotation of the Earth. The rotation axis is inclined to the orbital plane at an angle of 65°, almost equal to the angle of inclination of the earth's axis (66°.5). This means that the change of day and night, as well as the change of seasons on Mars proceed almost the same as on Earth. There is also climatic zones, similar to those on Earth: tropical (latitude of the tropics ±25°), two temperate and two polar (latitude of the polar circles ±65°).
However, due to the distance of Mars from the Sun and the rarefied atmosphere of the planet, the climate of the planet is much harsher than that of Earth. The year of Mars (687 Earth or 668 Martian days) is almost twice as long as the Earth’s, which means the seasons last longer. Due to the large eccentricity of the orbit (0.09), the duration and nature of the seasons of Mars are different in the northern and southern hemispheres of the planet.
Thus, in the northern hemisphere of Mars, summers are long but cool, and winters are short and mild (Mars is close to perihelion at this time), while in the southern hemisphere, summers are short but warm, and winters are long and harsh. On the disk of Mars back in the middle of the 17th century. dark and light areas were observed. In 1784
V. Herschel drew attention to seasonal changes the size of the white spots at the poles (polar caps). In 1882, the Italian astronomer G. Schiaparelli compiled detailed map Mars and gave a system of names for the details of its surface; highlighting among the dark spots “sea” (in Latin mare), “lakes” (lacus), “bays” (sinus), “swamps” (palus), “straits” (freturn), “springs” (fens), “ capes" (promontorium) and "regions" (regio). All these terms were, of course, purely conditional.
The temperature regime on Mars looks like this. During the daytime near the equator, if Mars is near perihelion, the temperature can rise to +25°C (about 300°K). But by evening it drops to zero and below, and during the night the planet cools even more, since the thin, dry atmosphere of the planet cannot retain the heat received from the Sun during the day.
average temperature on Mars it is significantly lower than on Earth - about -40° C. Under the most favorable conditions in summer, on the daytime half of the planet the air warms up to 20° C - a completely acceptable temperature for the inhabitants of the Earth. But winter night frost can reach up to -125° C. When winter temperature even carbon dioxide freezes into dry ice. Such sudden temperature changes are caused by the fact that the thin atmosphere of Mars is not able to retain heat for a long time. The first measurements of the temperature of Mars using a thermometer placed at the focus of a reflecting telescope were carried out back in the early 20s. Measurements by W. Lampland in 1922 gave an average surface temperature of Mars of -28°C; E. Pettit and S. Nicholson obtained -13°C in 1924. A lower value was obtained in 1960. W. Sinton and J. Strong: -43°C. Later, in the 50s and 60s. Numerous temperature measurements were accumulated and generalized at various points on the surface of Mars, in different seasons and times of day. From these measurements it followed that during the day at the equator the temperature could reach +27°C, but by the morning it could reach -50°C.
The Viking spacecraft measured the temperature near the surface after landing on Mars. Despite the fact that at that time it was summer in the southern hemisphere, the temperature of the atmosphere near the surface in the morning was -160°C, but by the middle of the day it had risen to -30°C. The atmospheric pressure at the surface of the planet is 6 millibars (i.e. 0.006 atmospheres). Clouds of fine dust constantly float over the continents (deserts) of Mars, which is always lighter than the rocks from which it is formed. Dust also increases the brightness of continents in red rays.
Under the influence of winds and tornadoes, dust on Mars can rise into the atmosphere and remain in it for quite a long time. Severe dust storms were observed in the southern hemisphere of Mars in 1956, 1971 and 1973. As shown by spectral observations in infrared rays, the main component in the atmosphere of Mars (as in the atmosphere of Venus) is carbon dioxide (CO3). Long-term searches for oxygen and water vapor at first did not give any reliable results, and then it was found that there is no more than 0.3% oxygen in the atmosphere of Mars.
The god of war, Mars, in the ancient Roman pantheon was considered the father of the Roman people, the guardian of fields and domestic animals, and then the patron of equestrian competitions. The fourth planet from the Sun is named after him. Probably, the blood-red appearance of the planet evoked associations with war and death among the first observers. They even received corresponding names - Phobos (“fear”) and Deimos (“horror”).
Red riddle
Each planet has its mysteries, but none of them intrigued earthlings as much as Mars. The unusual red appearance of the planet remained inexplicable for a long time; it was also interesting what the temperature was on Mars, and whether its color depended on this. Today, every schoolchild knows that the abundant content of iron minerals in the Martian soil gives it such a color. And in the past there were some questions to which the most inquisitive minds of earthlings sought answers.
Cold planet
In terms of age, this planet is the same as the Earth and the rest of its neighbors in the solar system. Scientists suggest that her birth occurred 4.6 billion years ago. And although not everything in the history of the planet’s development has yet been clarified, much has already been established, including what the temperature is on Mars.
Relatively recently, large thicknesses of ice deposits were discovered at the poles in both hemispheres. This is evidence that liquid water once existed on the planet. And the temperature of Mars may have been completely different. Many scientists assume that if there is ice on the surface, then water should remain in the rocks. And the presence of water is confirmation that there was once life here.
It has been established that the planet's atmosphere has a density 100 times less than that of Earth. But despite this, clouds and wind form in the layers of the Martian atmosphere. Huge dust storms sometimes rage above the surface.
What is the temperature on Mars is already known, and thanks to the data obtained, we can conclude that it is much colder on the red neighbor than on Earth. In the region of the poles, a temperature of -125 degrees Celsius was recorded in winter, and the highest in summer reaches +20 degrees in the equator region.
How is it different from Earth?
There are many differences between the planets, some of them quite significant. Mars is much smaller in size than Earth, twice as large. And the planet is located much further from the Sun: the distance to the star is almost 1.5 times further than that of our planet.
Since the mass of the planet is relatively small, it is almost three times less than on Earth. On Mars, as well as on our planet, there are different times years, but their duration is almost twice as long.
Unlike Earth, Mars, whose air temperature averages -30...-40°C, has a very rarefied atmosphere. Its composition is dominated by carbon dioxide, which suggests that the temperature on Mars near the surface does not change significantly throughout the day. For example, at noon it can be -18° C, and in the evening - already -63° C. At night, temperatures at the equator were recorded at 100 degrees below zero.
If you are going to spend a vacation on another planet, then it is important to learn about possible climate changes :) But seriously, many people know that most planets in our solar system have extreme temperatures that are unsuitable for quiet living. But what exactly are the temperatures on the surface of these planets? Below I offer a short overview of planetary temperatures solar system.
Mercury
Mercury is the planet closest to the Sun, so one would assume that it is constantly heated like a furnace. However, although the temperature on Mercury can reach 427°C, it can also drop to a very low level of -173°C. Such a large difference in the temperature of Mercury occurs because it lacks an atmosphere.
Venus
Venus, the second closest planet to the Sun, has the highest average temperatures of any planet in our solar system, regularly reaching temperatures of 460°C. Venus is so hot because of its proximity to the Sun and its thick atmosphere. The atmosphere of Venus consists of dense clouds containing carbon dioxide and sulfur dioxide. This creates a strong greenhouse effect that keeps the sun's heat trapped in the atmosphere and turns the planet into an oven.
Earth
Earth is the third planet from the Sun, and so far the only planet known to support life. The average temperature on Earth is 7.2°C, but it varies by large deviations from this indicator. The highest temperature ever recorded on Earth was 70.7°C in Iran. The most low temperature was, and it reaches -91.2°C.
Mars
Mars is cold because, firstly, it does not have an atmosphere to maintain a high temperature, and secondly, it is located relatively far from the Sun. Because Mars has an elliptical orbit (it gets much closer to the Sun at some points in its orbit), during the summer its temperature can deviate by up to 30°C from normal in the northern and southern hemispheres. The minimum temperature on Mars is approximately -140°C, and the highest is 20°C.
Jupiter
Jupiter does not have any solid surface since it is a gas giant, so it does not have any surface temperature. At the top of Jupiter's clouds the temperature is about -145°C. As you descend closer to the center of the planet, the temperature increases. At a point where the atmospheric pressure is ten times greater compared to that on Earth, the temperature is 21°C, which some scientists jokingly call “room temperature.” At the planet's core, temperatures are much higher, reaching approximately 24,000°C. For comparison, it is worth noting that Jupiter's core is hotter than the surface of the Sun.
Saturn
As on Jupiter, the temperature is upper layers Saturn's atmosphere remains very low - reaching approximately -175°C - and increases as it approaches the center of the planet (up to 11,700°C in the core). Saturn actually generates its own heat. It produces 2.5 times more energy than it receives from the Sun.
Uranus
Uranus is the most cold planet with the lowest recorded temperature being -224°C. Although Uranus is far from the Sun, this is not the only reason for its low temperature. All the other gas giants in our solar system emit more heat from their cores than they receive from the sun. Uranus has a core with a temperature of approximately 4737°C, which is only one-fifth the temperature of Jupiter's core.
Neptune
With temperatures reaching as low as -218°C in Neptune's upper atmosphere, this planet is one of the coldest in our solar system. Like the gas giants, Neptune has a much hotter core, which has a temperature of about 7000°C.
Below is a graph showing planetary temperatures in both Fahrenheit (°F) and Celsius (°C). Please note that Pluto has not been classified as a planet since 2006 (see below).
Atmospheric composition
The atmosphere of Mars is more rarefied than the air shell of the Earth, and consists of 95% carbon dioxide, about 4% nitrogen and argon. There is less than 1% oxygen and water vapor in the Martian atmosphere. The average atmospheric pressure at the surface is 160 times less than that of the Earth's surface.
The mass of the atmosphere changes greatly throughout the year due to condensation in winter time and evaporation in the summer, large volumes of carbon dioxide at the poles, in the polar caps.
Clouds and precipitation
There is very little water vapor in the Martian atmosphere, but low pressure and temperature it is in a state close to saturation and often gathers in clouds. Martian clouds are rather featureless compared to those on Earth.
Temperature
The average temperature on Mars is much lower than on Earth - about −40°C. Under the most favorable conditions in summer, on the daytime half of the planet, the air warms up to 20°C - a completely acceptable temperature for the inhabitants of the Earth. But on a winter night the frost can reach −125°C. At winter temperatures, even carbon dioxide freezes, turning into dry ice. Such sudden temperature changes are caused by the fact that the thin atmosphere of Mars is not able to retain heat for a long time. As a result of numerous temperature measurements at various points on the surface of Mars, it turns out that during the day at the equator the temperature can reach +27°C, but by the morning it drops to −50°C.
There are also temperature oases on Mars; in the areas of the Phoenix “lake” (solar plateau) and the land of Noah, the temperature difference ranges from −53°C to +22°C in summer and from −103°C to −43°C in winter. Thus, Mars is very cold world, however, the climate there is not much harsher than in Antarctica. When the first photographs from the surface of Mars, taken by Viking, were transmitted to Earth, scientists were very surprised to see that the Martian sky was not black, as expected, but pink. It turned out that dust hanging in the air absorbs 40% of the incoming sunlight, creating a color effect.
Dust storms and tornadoes
One of the manifestations of temperature differences is winds. Strong winds often blow over the surface of the planet, the speed of which reaches 100 m/s. Low gravity allows even thin air currents to raise huge clouds of dust. Sometimes quite large areas on Mars are covered in enormous dust storms. Most often they occur near the polar ice caps. A global dust storm on Mars prevented photography of the surface from the Mariner 9 probe. It raged from September to January 1972, raising about a billion tons of dust into the atmosphere at an altitude of more than 10 km. Dust storms most often occur during periods of great opposition, when summer in the southern hemisphere coincides with Mars' passage through perihelion.
Dust devils are another example of temperature-related processes on Mars. Such tornadoes are very common occurrences on Mars. They raise dust into the atmosphere and are caused by temperature differences. Reason: during the day, the surface of Mars heats up quite a lot (sometimes to positive temperatures), but at an altitude of up to 2 meters from the surface, the atmosphere remains just as cold. This difference causes instability, raising dust into the air - resulting in the formation of dust devils.
Seasons
Today it is known that of all the planets in the solar system, Mars is the most similar to Earth. Mars' rotation axis is tilted to its orbital plane by approximately 23.9°, which is comparable to Earth's 23.4° axial tilt, and Martian day practically coincide with those on Earth - that is why, like on Earth, the seasons change. Seasonal changes are most pronounced in the polar regions. In winter, the polar caps occupy a significant area. The boundary of the northern polar cap can move away from the pole by a third of the distance to the equator, and the boundary of the southern cap covers half of this distance. This difference is caused by the fact that in the northern hemisphere, winter occurs when Mars passes through the perihelion of its orbit, and in the southern hemisphere, when it passes through aphelion. Because of this, winter in the southern hemisphere is colder than in the northern hemisphere. And the length of each of the four Martian seasons varies depending on its distance from the Sun. Therefore, in the Martian northern hemisphere, winter is short and relatively “moderate”, and summer is long but cool. In the south, on the contrary, summers are short and relatively warm, and winters are long and cold.
With the onset of spring, the polar cap begins to “shrink,” leaving behind gradually disappearing islands of ice. At the same time, a so-called darkening wave is spreading from the poles to the equator. Modern theories it is explained by the fact that spring winds transport large masses of soil with different reflective properties along the meridians.
Apparently none of the caps disappear completely. Before Mars was explored using interplanetary probes, it was assumed that its polar regions were covered with frozen water. More accurate modern ground-based and space measurements have discovered the composition Martian ice also frozen carbon dioxide. In summer it evaporates and enters the atmosphere. The winds carry it to the opposite polar cap, where it freezes again. This cycle of carbon dioxide and the different sizes of the polar caps explain the variability in the pressure of the Martian atmosphere.
The relief of the Martian surface is complex and has many details. Dry riverbeds and canyons on the surface of Mars have given rise to speculation about the existence of an advanced civilization on Mars - for more details, see the article Life on Mars.
The typical Martian landscape resembles an terrestrial desert, and the surface of Mars has a reddish tint due to the increased content of iron oxides in Martian sand.
Links
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See what “Climate of Mars” is in other dictionaries:
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Mars is now dry and cold climate(left), but in the early stages of the planet's evolution there most likely was liquid water and dense atmosphere(on right).
Studying
Observation history
Current observations
Weather
Temperature
The average temperature on Mars is significantly lower than on Earth: −63°C. Since the atmosphere of Mars is very rarefied, it does not smooth out daily fluctuations in surface temperature. Under the most favorable conditions in summer, on the daytime half of the planet the air warms up to 20 ° C (and at the equator - up to +27 ° C) - a completely acceptable temperature for the inhabitants of the Earth. The maximum air temperature recorded by the Spirit rover was +35 °C. But winter at night, frost can reach even at the equator from −80 °C to −125 °C, and at the poles the night temperature can drop to −143 °C. However, daily temperature fluctuations are not as significant as on the atmosphereless Moon and Mercury. There are temperature oases on Mars, in the areas of the Phoenix Lake (solar plateau) and land of Noah The temperature difference ranges from −53°С to +22°С in summer and from −103°С to −43°С in winter. Thus, Mars is a very cold world, the climate there is much harsher than in Antarctica.
| Climate of Mars, 4.5ºS, 137.4ºE (from 2012 to today [ When?]) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Index | Jan. | Feb. | March | Apr. | May | June | July | Aug. | Sep. | Oct. | Nov. | Dec. | Year |
| Absolute maximum, °C | 6 | 6 | 1 | 0 | 7 | 23 | 30 | 19 | 7 | 7 | 8 | 8 | 30 |
| Average maximum, °C | −7 | −18 | −23 | −20 | −4 | 0 | 2 | 1 | 1 | 4 | −1 | −3 | −5,7 |
| Average minimum, °C | −82 | −86 | −88 | −87 | −85 | −78 | −76 | −69 | −68 | −73 | −73 | −77 | −78,5 |
| Absolute minimum, °C | −95 | −127 | −114 | −97 | −98 | −125 | −84 | −80 | −78 | −79 | −83 | −110 | −127 |
| Source: Centro de Astrobiología, Mars Science Laboratory Weather Twitter | |||||||||||||
Atmosphere pressure
The atmosphere of Mars is more rarefied than the air shell of the Earth, and consists of more than 95% carbon dioxide, and the oxygen and water content is a fraction of a percent. The average atmospheric pressure at the surface is on average 0.6 kPa or 6 mbar, which is 160 less than the Earth's or equal to the Earth's at an altitude of almost 35 km from the Earth's surface). Atmosphere pressure undergoes strong daily and seasonal changes.
Clouds and precipitation
There is no more than a thousandth of a percent of water vapor in the Martian atmosphere, but according to the results of recent (2013) studies, this is still more than previously thought, and more than in the upper layers of the Earth's atmosphere, and at low pressure and temperature it is in in a state close to saturation, so it often gathers in clouds. As a rule, water clouds form at altitudes of 10-30 km above the surface. They are concentrated mainly at the equator and are observed almost throughout the year. Clouds observed on high levels atmosphere (more than 20 km), are formed as a result of CO 2 condensation. The same process is responsible for the formation of low (at an altitude of less than 10 km) clouds in the polar regions in winter, when the atmospheric temperature drops below the freezing point of CO 2 (-126 °C); in summer, similar thin formations of ice H 2 O are formed
Formations of a condensation nature are also represented by fogs (or haze). They often stand above lowlands - canyons, valleys - and at the bottom of craters during the cold season.
Snowstorms can occur in the atmosphere of Mars. In 2008, the Phoenix rover observed virgu in the polar regions - precipitation under clouds that evaporates before reaching the surface of the planet. According to initial estimates, the rate of precipitation in Virga was very low. However, recent (2017) modeling of Martian atmospheric phenomena showed that at mid-latitudes, where there is a regular cycle of day and night, clouds cool sharply after sunset, and this can lead to snowstorms, during which particle speeds can actually reach 10 m/s. Scientists admit that strong winds combined with low clouds (usually Martian clouds form at an altitude of 10-20 km) can lead to snow falling on the surface of Mars. This phenomenon is similar to terrestrial microbursts - squalls of downward wind with a speed of up to 35 m/s, often associated with thunderstorms.
Snow has indeed been observed more than once. So, in the winter of 1979, a thin layer of snow fell in the Viking-2 landing area, which remained for several months.
Dust storms and tornadoes
A characteristic feature of the atmosphere of Mars is the constant presence of dust, particles of which have a size of about 1.5 mm and consist mainly of iron oxide. Low gravity allows even thin air currents to raise huge clouds of dust to a height of up to 50 km. And winds, which are one of the manifestations of temperature differences, often blow over the surface of the planet (especially in late spring - early summer in the southern hemisphere, when the temperature difference between the hemispheres is especially sharp), and their speed reaches 100 m/s. In this way, extensive dust storms are formed, long observed in the form of individual yellow clouds, and sometimes in the form of a continuous yellow veil covering the entire planet. Most often, dust storms occur near the polar caps; their duration can reach 50-100 days. A faint yellow haze in the atmosphere is usually observed after large dust storms and is easily detected by photometric and polarimetric methods.
Dust storms, clearly visible in images taken from orbital vehicles, turned out to be barely noticeable when photographed from landers. The passage of dust storms in the landing sites of these space stations was recorded only by a sharp change in temperature, pressure and a very slight darkening of the general background of the sky. The layer of dust that settled after the storm in the vicinity of the Viking landing sites amounted to only a few micrometers. All this indicates a rather low bearing capacity of the Martian atmosphere.
From September 1971 to January 1972, a global dust storm occurred on Mars, which even prevented photography of the surface from the Mariner 9 probe. The mass of dust in the atmospheric column (with an optical depth of 0.1 to 10), estimated during this period, ranged from 7.8⋅10 -5 to 1.66⋅10 -3 g/cm 2 . Thus, total weight dust particles in the atmosphere of Mars during the period of global dust storms can reach up to 10 8 - 10 9 tons, which is comparable to the total amount of dust in earth's atmosphere.
Question about water availability
For a stable existence clean water in liquid state temperature And The partial pressure of water vapor in the atmosphere should be above the triple point on the phase diagram, whereas now they are far from the corresponding values. Indeed, research conducted by the Mariner 4 spacecraft in 1965 showed that there is currently no liquid water on Mars, but data from NASA's Spirit and Opportunity rovers indicate the presence of water in the past. On July 31, 2008, ice water was discovered on Mars at the landing site of NASA's Phoenix spacecraft. The device discovered ice deposits directly in the ground. There are several facts to support the claim that water was present on the planet's surface in the past. Firstly, minerals were found that could only be formed as a result of prolonged exposure to water. Secondly, very old craters have been practically erased from the face of Mars. The modern atmosphere could not cause such destruction. A study of the rate of formation and erosion of craters made it possible to establish that wind and water destroyed them most strongly about 3.5 billion years ago. Many ravines are approximately the same age.
NASA announced on September 28, 2015 that seasonal flows of liquid salt water currently exist on Mars. These formations manifest themselves in the warm season and disappear in the cold season. Planetary scientists came to their conclusions by analyzing high-quality images obtained by the High Resolution Imaging Science Experiment (HiRISE) scientific instrument of the Mars Reconnaissance Orbiter (MRO).
On July 25, 2018, a report was released about the discovery, based on research by the MARSIS radar. The work showed the presence of a subglacial lake on Mars, located at a depth of 1.5 km under the ice of the South Polar Cap (on Planum Australia), about 20 km wide. This became the first known permanent body of water on Mars.
Seasons
As on Earth, on Mars there is a change of seasons due to the inclination of the rotation axis to the orbital plane, so in winter the polar cap grows in the northern hemisphere, and almost disappears in the southern hemisphere, and after six months the hemispheres change places. Moreover, due to the rather large eccentricity of the planet’s orbit at perihelion ( winter solstice in the northern hemisphere) it receives up to 40% more solar radiation than in aphelion, and in the northern hemisphere the winters are short and relatively moderate, and the summers are long but cool, in the southern hemisphere, on the contrary, the summers are short and relatively warm, and the winters are long and cold . In connection with this, the southern cap in winter expands to half the pole-equator distance, and the northern cap only to a third. When summer begins at one of the poles, carbon dioxide from the corresponding polar cap evaporates and enters the atmosphere; the winds carry it to the opposite cap, where it freezes again. This creates a cycle of carbon dioxide, which, along with the different sizes of the polar caps, causes the pressure of the atmosphere of Mars to change as it orbits the Sun. Due to the fact that in winter up to 20-30% of the entire atmosphere freezes in the polar cap, the pressure in the corresponding area drops accordingly.
Changes over time
As on Earth, the climate of Mars underwent long-term changes and in the early stages of the planet's evolution was very different from what it is today. The difference is that main role in the cyclic changes in the Earth's climate, changes in the eccentricity of the orbit and the precession of the rotation axis play a role, while the inclination of the rotation axis remains approximately constant due to the stabilizing effect of the Moon, while Mars, without such large satellite, can undergo significant changes in the inclination of its rotation axis. Calculations have shown that the inclination of Mars' rotation axis, which is now 25° - approximately the same value as that of the Earth - was 45° in the recent past, and on a scale of millions of years could fluctuate from 10° to 50°.
