As we physicists know, the color and brightness of the sky are determined not by the color of the "firmament", but by the light of the Sun scattered in the atmosphere (G.S. Landsberg, Elementary textbook of physics. Volume 3. Oscillations and waves. Optics. Atomic and nuclear physics § 171. The color of the sky and dawns. p. 402.) . Since it is the substance of the atmosphere that scatters and re-radiates the light of the Sun, the brightness of the sky is directly proportional to the amount of matter in the atmosphere on which it is scattered. sunlight. This obvious fact underlies photometric methods research, for example, the concentration of substances.
The total amount of matter in the atmosphere, which determines the color and brightness of the sky, is easily calculated from surface pressure. Consider a surface area, say a circle with an area of 1m 2, and imagine a cylinder with vertical walls, based on this circle (actually it will be frustum, however, is insignificant). Gas weight, i.e. the force with which this gas presses on the support is equal to total mass gas in that cone multiplied by gravity. (Actually, strictly speaking, it is necessary to take into account the change in gravity with height. Let's evaluate whether this should be taken into account or whether the calculations can be simplified. Let's take the radius of Mars as 3389.5 km - when rising to a height of 10 km, gravity will drop by only 0.6%, and when rise to a height of 100 km - by 5%, for the Earth the influence is even less due to twice the radius, and since the bulk of the atmosphere both on Earth and on Mars is concentrated in the first 10 km, we can safely ignore the change in gravity with height and instead of integrating in terms of height, we restrict ourselves to a banal suggestion.)
However, this same force (pressure of the gas cone on the supporting surface) is equal to the gas pressure multiplied by the area. On the surface of Mars, the pressure is 6.1 mbar, 162 times less than on Earth. Gravity (free fall acceleration) on the surface of Mars is 3.711 m/s 2 , i.e. 2.6 times less than on Earth. Consequently, the gas in the atmosphere of Mars (by mass) is 62 times less than on Earth.
Let's try to estimate the number of molecules in the Martian atmosphere. The main part of the atmosphere of Mars is carbon dioxide with a molar mass of 44, and air (a mixture of nitrogen and oxygen) has about 29. Therefore, the number of molecules that scatter light, giving color and brightness to the Martian sky, is even 1.5 times less. Yes, air and carbon dioxide scatter and absorb light of different wavelengths differently (especially in the IR region; this property carbon dioxide used in optical sensors of carbon dioxide concentration), but in the visible range there is no fundamental difference, and this is no longer important.
In addition, it must be taken into account that Mars is one and a half times farther from the Sun than the Earth, respectively, the illumination of Mars sunlight smaller than the earth by 2.32 times. If you compare the brightness of the sky on Mars with the surface of Mars, then the factor of distance from the Sun does not need to be taken into account, you can simply make the shutter speed 2.32 times longer than on Earth to get a normal exposure. But if we compare the brightness of the sky on Mars with the brightness of the stars, then this will have to be taken into account. The total brightness of the sky on Mars relative to the light of stars that can be taken as a standard will be 140-215 times less than on Earth (and this is without taking into account the attenuation of starlight by the atmosphere - for example, for the Crimean Observatory, the average transparency coefficient of the atmosphere is 0.73, and for Mars, the transparency of the atmosphere will be approximately 0.995).
Those. simple estimates show that the brightness of the sky on Mars is 2 orders of magnitude less than on Earth, i.e. it's almost black. But what color it will turn out if you shoot the sky on Mars, increasing the exposure time by 200 times - I don’t know, this is a completely different question.
Actually, these estimates are confirmed by observations on Earth. Since gravity on Earth is 2.6455 times greater than on Mars, the same amount of atmospheric gas overhead, which determines the color of the sky, is achieved at a pressure of 16 mbar at an altitude of 32 km. Here are the words of Evgeny Andreev, who jumped from a height of 25 km: "I turned over on my back so that the heat transfer was less, and - forward! I was struck by the sky of a thick ink color and the stars - close, close. I glanced down over my shoulder, and there was blueness, a bright orange sun ... Beauty!"
Here is a photo taken at an altitude of 20 km:
So that there is too little material in the atmosphere of Mars to give the sky anything other than black., so the sky on Mars is not blue, not orange, but almost black with stars clearly visible (to the human eye) even during the day. In photographs in which the soil illuminated by the Sun is visible, the stars will not be visible due to the small dynamic range of both photographic film and semiconductor matrices used for photography and video filming. (When NASA needs it, they will be visible.) But in photographs where the ground is visible normally, not overexposed, the sky should be almost black, and only a more or less light stripe along the horizon.
I don't know if the US delivered a rover to Mars or not. Maybe they delivered, but for some reason they don’t want to share real pictures for free. I can not know. But here are the images that NASA passes off as images taken on Mars, and in which the sky is not black, is an outright fake. 
First, the incredibly bright sky. Secondly, the mountains are just as incredibly foggy. For the earth's atmosphere, the picture looks quite natural, but not for the 60 times rarefied Martian atmosphere. Jerry White video
I am very ashamed of the scientists who have frank lies put in their noses, but they do not react to it in any way. It is doubly ashamed of those who cover up the lies of NASA, and even more so, they are trying to investigate something out of these fakes. Alas, His Majesty the Dollar completely ousted the concepts of scientific truth and reliability from science.
How many hopes connected humanity with the conquest of space! Alas, in most cases, hopes remained hopes. Of all the space objects, only the Moon has been visited, even Mars has not yet been reached, so one can only dream of interplanetary travel. We dream too! It's so interesting what we could see on other planets? Let's say, what is the sky?
First, let's remember why on Earth it is blue. This is explained by the properties of the atmosphere, during the passage through which it is this part of the solar spectrum that is most scattered, while the rest are absorbed. Accordingly, with a different atmosphere, the color of the sky will be different ... if it exists at all!
On Mercury, for example, there is no atmosphere at all, there is nothing to scatter light, so the sky is always black, even during the day. Still, you can’t confuse day and night there: you won’t see stars during the day, the Sun overshadows them with its light, because it is much closer to Mercury than to Earth.
On Venus, you will never be able to see either the stars or the Sun, because the atmosphere is too dense, and it consists mainly of carbon dioxide and nitrogen. Such an atmosphere absorbs green rays and blue, red and yellow manage to overcome it, and therefore the sky on Venus has yellow tint, and at the zenith - dark orange. The picture makes a very gloomy impression.
The atmosphere of Mars is rarefied compared to Earth, but there is a lot of dust in it. Its particles scatter light, so that during the day the sky is bright there, as on Earth, and the stars are not visible. The rarefied atmosphere still cannot scatter light enough to turn the sky blue, and Martian dust, rich in iron oxides, has a reddish tint, so the sky on Mars is reddish-yellow. It becomes blue only at sunset, next to the Sun, while the rest of it becomes pink.
On Jupiter, the sky is blue, only darker than on Earth: after all, it is much further from the Sun. see there blue sky you can only be above the clouds that always cover Jupiter. There are no clear days. As for the clouds, they are either white (from ammonia) or reddish-orange. These clouds not only look unusual, but also smell terrible due to sulfur impurities. Several satellites can be seen in the sky of Jupiter, and Io will be the most noticeable - slightly larger than our moon.
On Saturn, the sky will be blue, like on Earth, but only in upper layers atmosphere. With a deeper dive, it will “turn yellow” for the observer. Of course, the most remarkable detail of the Saturnian sky is the famous rings of Saturn! From upper layers atmosphere, they will be clearly visible. Just don’t look from the equator, you won’t see anything there, because the rings there are quite thin - only one kilometer thick. From other regions of the planet, you will see a silvery arc passing through the entire sky, which continues to be illuminated even after sunset.
The atmosphere of Uranus consists of hydrogen and helium, and in the upper layers there is also methane, which perfectly reflects green rays and blue ones, but it absorbs red ones. From this, the sky on Uranus is the color of aquamarine.
The atmosphere of Neptune is similar in composition to that which encircles Uranus, but the quantitative ratio of gases is somewhat different and the color of the sky is blue.
In a word, on all the planets of the solar system there is something to see, at least in the sky! And at least for this it is worth flying to them.
Staged shots
In fact, most often spacecraft exploring solar system, take black-and-white pictures - such cameras are simpler, more reliable and cheaper. In order to get a color image, rovers or probes take three black-and-white frames: through red, green and blue filters, and then compose a color image from them. By the way, this is how, at the beginning of the 20th century, the world's first color photographs were obtained by a great photography enthusiast and inventor Sergei Prokudin-Gorsky. His camera had three lenses that simultaneously took three black-and-white pictures through filters, and the color image was “synthesized” later, in the projector.
Despite the "roundabout" method of production, the color images obtained in this way completely convey real colors. So where does the blue sunset on Mars come from?
Physics and dust
The fact is that the atmospheres of Mars and Earth are very different. On Mars, it is noticeably less dense and very dusty. Dust contains very tiny particles, the size of which is comparable to the wavelength of light. During the day, the smallest dust particles absorb the blue part of the sunlight spectrum and the sky on Mars has the same reddish tint as its entire surface. When the Sun sets, the path that light takes in the atmosphere of the planet becomes longer and another effect becomes dominant - Rayleigh scattering of light. At the same time, blue light is scattered more strongly in the Martian atmosphere. It is because of this that we see a blue glow around the setting Sun on Mars.
Typical Martian sunset. Photo: NASA/JPL-Caltech/MSSS/Damia Bouch
Other skies
Mars is part of an elite club of four atmospheric celestial bodies whose surface and sky we have been able to see in color. The other two members of the club are Venus and Titan, and, of course, our Earth.
On March 1, 1983, the Venera-13 probe landed on the surface of Venus, which was able to work at a temperature of 456 degrees Celsius and a pressure of 92 atmospheres for 127 minutes. The unlucky Venus was not the first spacecraft to return images from the surface of our nearest neighbor in the solar system, but it was the first color image. The descent vehicle carried two "color" telephotometric cameras TFZL-077. They obtained the image by taking pictures through three color filters - blue, green and red.
The reference color scale was in the field of view of the Venera-13 panoramic cameras. Having received synthesized color images, terrestrial scientists were able to correct them on this scale. The target of the shooting was the surface of the planet, but the yellowing sky is visible in the corners of the panoramas. Four days later, on March 5, color images were taken by the Venera-13 stand-in, the Venera-14 apparatus, which worked on the surface for only 57 minutes. The yellow-green color of Venus is also due to Rayleigh scattering. However, according to Alexander Rodin, Deputy Head of the Laboratory for High-Resolution Infrared Spectroscopy of Planetary Atmospheres at Moscow Institute of Physics and Technology, this color is due, firstly, to the increased density of the Venusian atmosphere, and secondly, to the presence of a large number sulfuric acid.
Fragments of the sky are visible along the edges of the Venusian surface. Photo: IKI RAS
The "colored" conquest of the next celestial body with the atmosphere had to wait more than ten years. On January 14, 2005, the ESA-built Huygens lander, delivered to the Saturn system by NASA's Cassini probe, landed on the surface of Saturn's largest moon, Titan.
It was long thought to be the largest moon in the solar system, but Voyager studies in the 1980s showed that Titan appears larger than it is due to the dense methane atmosphere that was mistaken for the moon's surface. But even minus the atmosphere, this is a rather large celestial body: among the satellites, only Jupiter's Ganymede overtakes it. Titan is not only bigger than our Moon, but also Mercury and Pluto.
Huygens worked 147 minutes during the parachute descent and transmitted signals from the surface for another 72 minutes, having managed to send 700 megabytes of information to Earth, including 350 images, some of which were in color.
In the photographs, Titan looks, though lifeless, but quite peaceful. In fact, a person would not have lasted there for even a few seconds. Photo: NASA/JPL/ESA/University of Arizona
The spacecraft's cameras captured the satellite's yellow-brown surface of frozen hydrocarbons, freshly washed by methane rain (the climate on Titan is not very good). The sky on the Saturnian moon is also yellow-brown, and the satellite itself is yellow-green in the pictures. And here again the same scattering "works", only on other gases.
After astronomers photographed the landscape on Titan, there were no “atmospheric” objects with colored skies left in the solar system (giant planets, which consist of gas and liquid, do not count). On all other celestial bodies in the solar system, from Mercury to Pluto, the sky will be black - even in black and white, even in color photography. There is no significant atmosphere, which means that there is nothing to scatter sunlight on.
In science fiction films, we see other worlds with skies, it seems, of all the colors of the rainbow. But scientists still cannot answer the question of what color the sky can really be on planets outside the solar system (the so-called exoplanets). We can only guess what kind of atmospheres these planets have: more than three thousand exoplanets have been discovered today, and most of them are in star systems that are nothing like the Solar. And the very light of the stars that illuminate these planets may not be the same as the light from the Sun: red dwarfs, blue giants, white giants, and even almost purple (in the visible range) brown dwarfs can have planets.
As we physicists know, the color and brightness of the sky are determined not by the color of the "firmament", but by the light of the Sun scattered in the atmosphere (G.S. Landsberg, Elementary textbook of physics. Volume 3. Oscillations and waves. Optics. Atomic and nuclear physics § 171. The color of the sky and dawns, p. 402.). Since it is the substance of the atmosphere that scatters and re-radiates the light of the Sun, the brightness of the sky is directly proportional to the amount of matter in the atmosphere on which sunlight is scattered. This obvious fact underlies photometric research methods, for example, the concentration of substances.
The total amount of matter in the atmosphere, which determines the color and brightness of the sky, is easily calculated from surface pressure. Consider a surface area, say, a circle with an area of 1m2, and imagine a cylinder with vertical walls resting on this circle (in fact, it will be a truncated cone, however, it is not essential). Gas weight, i.e. the force with which this gas presses on ...
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AT this moment there are many photographs of Mars, but not all of them allow us to judge the color of the sky on this planet. Many of them have too high a white balance, so our vision does not allow us to distinguish the contrasts in these photographs. Fortunately, there are quite interesting studies in which scientists are trying to distinguish the colors in the sky of Mars and explain them with physical patterns.
As part of the Mars Exploration Rover program, NASA scientists delivered the Spirit, Oppotunity and Bell III rovers to the red planet. The rovers were equipped with Pancam Instrument panoramic cameras. Scientists have obtained radiometric calibrated images that can be used to determine the color of the sky. The image data has been transformed into physical quantities(flux and radiance) taking into account the spectral sensitivity of the camera and filters, solar radiation reaching the surface of Mars, and other factors. Spirit and Oppotunity photographed...
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Here the material of Keith Laney caught my eye, who discovered interesting nuances regarding the photographs delivered from the Spirit rover. Material in attachment.
Look at the photo
The NASA logo is blue, and in the photo (bottom right) it is some kind of brown-brick.
The principle of operation is simple - four control color marks; white disk; axis showing the light source.
The specialist draws attention to the difference between the control photo taken on Earth and the photo taken on Mars.
Those. on the face of a problem with the correct color reproduction of the image. What is it, features of the operation of cameras and matrices, or something else?
From NASA's point of view, Mars should look something like this:
There is an earlier photo, 1997.
This is the photo that is here:
This is a close-up of the sunset on Sol 24 as seen by the Imager for Mars Pathfinder. The red sky in the background and...
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Various landers have shown us a myriad of shades in photographs from Mars. Oddly enough, simple photographic adjustments can turn many of them earth-like. And at the same time, reverse transformations can turn the Earth's desert into Mars. Some say that the brown-orange sky is due to a planetary dust storm... even if there is no storm. But the most interest Ask Is there a sky on Mars at all?
Video published by Jera White and provided with a Russian interlinear, which is activated by pressing the SS
Caught red-handed!
At the beginning of July 2011, the BBC One TV channel of the British state television aired the next edition of the monthly program "Night Sky", dedicated to astronomy and space exploration.
In the film, Steve Squyres of Cornell University is shown working on a laptop, behind which are two very large monitors placed side by side. They are quite...
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Sky color on other planets
Published on 30.11.-0001 02:30Once we already talked about why the color of the earth's sky is blue during the day and slightly red at sunset or sunrise. What color are the skies on other planets? How will we see the Sun if we fly to some other planet in our solar system? Today we will make a big and very interesting journey through the planets of the solar system, fly to some interesting satellites of the planets and look at different extraterrestrial skies. Let's fly!
Let's start with Mercury. Mercury is an extremely hot world, because it is very close to the Sun, and it does not have an atmosphere that shields it from the heat of the sun. The absence of an atmosphere is what determines what the sky of Mercury looks like. The stars on Mercury are visible only at night, during the day they are not visible due to the fact that the Sun shines very brightly and outshines the stars with its brilliance.
There is a very interesting feature Mercurial sky. Once a Mercury year for...
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Sky color on Mars
During sunrise and sunset, the Martian sky at the zenith has a reddish-pink color, and in close proximity to the disk of the Sun - from blue to purple, which is completely opposite to the picture of earthly dawns.
Sunset on Mars. At noon, the sky of Mars is yellow-orange. The reason for these differences from colors terrestrial sky - the properties of a thin, rarefied atmosphere containing suspended dust of Mars. On Mars, Rayleigh scattering of rays (which on Earth is the cause of blue color sky) plays an insignificant role, its effect is weak. Presumably, the yellow-orange coloration of the sky is also caused by the presence of 1% magnetite in dust particles constantly suspended in the Martian atmosphere and raised by seasonal dust storms. Twilight begins long before sunrise and lasts long after sunset. Sometimes the color of the Martian sky takes on purple hue as a result of light scattering on microparticles of water ice in clouds (the latter is quite rare ...
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What color is the sky on Mars? Astrophysicist Santiago Pérez-Hoyos on the atmosphere of Mars, the Purkin effect and the perception of the color of the Martian sky by the human eye At the moment there are many photographs of Mars, but not all of them allow us to judge the color of the sky on this planet. Many of them have too high a white balance, so our vision does not allow us to distinguish the contrasts in these photographs. Fortunately, there are quite interesting studies in which scientists are trying to distinguish the colors in the sky of Mars and explain them with physical patterns. As part of the Mars Exploration Rover program, NASA scientists delivered the Spirit, Oppotunity and Bell III rovers to the red planet. The rovers were equipped with Pancam Instrument panoramic cameras. Scientists have obtained radiometric calibrated images that can be used to determine the color of the sky. The image data was transformed into physical quantities (flux and radiance) taking into account the spectral sensitivity of the camera and filters, solar radiation,...
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Staged shots
In fact, most often spacecraft exploring the solar system take black and white pictures - such cameras are simpler, more reliable and cheaper. In order to get a color image, rovers or probes take three black-and-white frames: through red, green and blue filters, and then compose a color image from them. By the way, this is how the great photography enthusiast and inventor Sergei Prokudin-Gorsky obtained the world's first color photographs at the beginning of the 20th century. His camera had three lenses that simultaneously took three black-and-white pictures through filters, and the color image was “synthesized” after that, in the projector.
Despite the "roundabout" method of production, the color images obtained in this way fully convey real colors. So where does the blue sunset on Mars come from?
Physics and dust
The fact is that the atmospheres of Mars and Earth are very different. On Mars, it is noticeably less dense and very dusty. The dust contains...
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In the Natural Sciences section, the question is what color is the sky on Mars? set by the author User deleted best answer is The atmosphere of Mars is extremely rarefied compared to the earth (0.6%). And during the day, the sky on Mars would have to be almost jet black, like on the Moon, with a slight purple tint. But it is quite bright, or pale pink, or reddish in color. Again, dust is to blame. The dust itself is red. She, illuminated by the sun, we see in the daytime sky.
link
But at sunset, the lighting conditions change. The dust is illuminated from the side of the setting Sun, and we see, as it were, the night side of the dust. It almost ceases to contribute to the color of the sky. But the scattering effect, as in the earth's atmosphere, continues to work. This is how the blue hue of the sky appears in the direction of the setting Sun
Answer from 2 answers[guru]
Hello! Here is a selection of topics with answers to your question: what color is the sky on Mars?
Answer from Igor[guru]
Sky color on Mars
During sunrise and sunset...
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The sunset video above was taken by the Opportunity rover, which has been roaming the Martian landscape for over 10 years.
When the Sun sets or rises on Earth, it shrinks like a melon due to atmospheric refraction (refraction). The thick layer of air adjacent to the horizon bends the Sun's light upward, pushing the bottom of the solar disk into the upper half, which is less subject to refraction because it is higher. As soon as the Sun rises high enough and we are already looking at it through a smaller layer of the atmosphere, the refraction decreases and the disk becomes round again.
You can watch videos of Martian sunsets many times, but the shape of the Sun will not change. Guess why? Because the air is too thin for refraction to be any noticeable.
Twilight lingers longer on the Red Planet as dust suspended in the stratosphere reflects light from the Sun for two or more hours after sunset.
So just...
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On our planet, the sky is blue because the earth's atmosphere scatters light best in the blue spectrum.
On other space objects, the compositions of the atmospheres differ from those on the earth or are absent altogether, therefore the sky on other planets differs significantly. The Moon, Mercury and Pluto have no atmosphere. And nothing scatters the rays of light. Therefore, the sky on these celestial bodies is black and the stars there are very bright.
Venus has an atmosphere, and it does not scatter green and blue rays. Therefore the sky on Venus yellow color, near the horizon has gray shade, and orange at the zenith.
The Martian sky is yellow-orange. This is because there is a lot of red dust in the atmosphere of the planet. During sunset and sunrise, the sky on Mars Pink colour, and on the horizon it changes from purple to blue.
The color of the sky of Saturn, as well as on Earth, is blue. And just like on our planet, the atmosphere does not scatter the red part of the solar ...
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The photographs taken by the landers operating on Mars are similar to some " keyhole", through which we can observe the cold harsh world of the Red Planet. This world is deadly for us, but someday people will walk on red stones and look at the Earth from the Martian surface. The topic of this article is the Martian sky and Martian "astronomy".
Bright white dot in this picture taken by the panoramic camera of the Spirit rover - the Sun.
Sunset in Ares Vallis in July 1997 at 16:10 local solar time. The colors of the image are close to true.
Sunset, Mars Pathfinder image.
The first minute after sunset on Mars.
In this image taken by the rover's panoramic camera...
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The photographs taken by the landers operating on Mars are like a kind of "keyhole" through which we can observe the cold, harsh world of the Red Planet. This world is deadly for us, but someday people will walk on red stones and look at the Earth from the Martian surface. The topic of this article is the Martian sky and Martian "astronomy".
The bright white dot in this image taken by the Spirit rover's panoramic camera is the Sun.
Sunset in Ares Vallis in July 1997 at 16:10 local solar time. The colors of the image are close to true.
Sunset, Mars Pathfinder image.
This image taken by the Spirit rover's panoramic camera on May 19, 2005 (Sol 489) shows the sunset approaching the rim of Gusev crater. The colors of the image are similar to what the human eye would see, but their intensity is slightly exaggerated.
Twilight in the Gusev crater, taken on the evening of April 23, 2005 (sol 464). The colors of the picture are close to those that a person would see. The bluish color of the sky at the site of the setting Sun would be seen exactly as shown in this image, but the redness of the sky further from sunset is somewhat exaggerated.
The little star in the center of the Martian night sky is our Earth.
An image taken on April 29, 2005 (Sol 449) by the Opportunity rover shows the Martian sky about an hour after sunset, during twilight, when the stars begin to appear. A dim dot near the center is not a star, but our home planet.
The ground in the image appears somewhat elongated, which is explained by its movement during the shooting.
Before us is "the abyss, full of stars" such as it can be seen from Mars. Due to the daily rotation of Mars, the stars stretched into tracks.
An image of the moons of Mars. Here, in addition to Phobos and Deimos, the Pleiades and Aldebaran are present. Image taken by Spirit on August 30, 2005 (Sol 590). The right image is an enlarged view accompanied by captions.
Phobos is visible from the surface of Mars as an object approximately three times smaller than full moon. The orbital time of Phobos around the planet is 7 hours 39 minutes. The smaller Martian moon, Deimos, takes 30 hours and 12 minutes to orbit Mars.
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