Instruct: Given a question, retrieve relevant passages that can help answer the question.
Query: What is the temperature on Mars?
Differing in situ values have been reported for the average temperature on Mars,[21] with a common value being −63°C (210K; −81°F).[22][23] Surface temperatures may reach a high of about 20°C (293K; 68°F) at noon, at the equator, and a low of about −153°C (120K; −243°F) at the poles.[24] Actual temperature measurements at the Viking landers' site range from −17.2°C (256.0K; 1.0°F) to −107°C (166K; −161°F). The warmest soil temperature estimated by the Viking Orbiter was 27°C (300K; 81°F).[25] The Spirit rover recorded a maximum daytime air temperature in the shade of 35°C (308K; 95°F), and regularly recorded temperatures well above 0°C (273K; 32°F), except in winter.[26]
As observed by the Viking spacecraft from the surface,[28] "during a global dust storm the diurnal temperature range narrowed sharply, from 50° Celsius to only about ten degrees, and the wind speeds picked up considerably—indeed, within only an hour of the storm's arrival they had increased to 17m/s (61km/h), with gusts up to 26m/s (94km/h). Nevertheless, no actual transport of material was observed at either site, only a gradual brightening and loss of contrast of the surface material as dust settled onto it." On June 26, 2001, the Hubble Space Telescope spotted a dust storm brewing in Hellas Basin on Mars (pictured right). A day later the storm "exploded" and became a global event. Orbital measurements showed that this dust storm reduced the average temperature of the surface and raised the temperature of the atmosphere of Mars by 30K.[29] The low density of the Martian atmosphere means that winds of 18 to 22m/s (65 to 79km/h) are needed to lift dust from the surface, but since Mars is so dry, the dust can stay in the atmosphere far longer than on Earth, where it is soon washed out by rain. The season following that dust storm had daytime temperatures 4K below average. This was attributed to the global covering of light-colored dust that settled out of the dust storm, temporarily increasing Mars' albedo.[57]
Using a vacuum thermocouple attached to the Hooker Telescope at Mount Wilson Observatory, in 1924 the American astronomers Seth Barnes Nicholson and Edison Pettit were able to measure the thermal energy being radiated by the surface of Mars. They determined that the temperature ranged from at the pole up to at the midpoint of the disk (corresponding to the equator). Beginning in the same year, radiated energy measurements of Mars were made by American physicist William Coblentz and American astronomer Carl Otto Lampland. The results showed that the night time temperature on Mars dropped to , indicating an "enormous diurnal fluctuation" in temperatures. The temperature of Martian clouds was measured as . In 1926, by measuring spectral lines that were redshifted by the orbital motions of Mars and Earth, American astronomer Walter Sydney Adams was able to directly measure the amount of oxygen and water vapor in the atmosphere of Mars. He determined that "extreme desert conditions" were prevalent on Mars. In 1934, Adams and American astronomer Theodore Dunham, Jr. found that the amount of oxygen in the atmosphere of Mars was less than one percent of the amount over a comparable area on Earth.
HABIT (HabitAbility, Brine Irradiation and Temperature) is an instrument designed to harvest water from the Mars atmosphere, an experiment that might pave the way to future water farms on Mars. The instrument will be placed onboard ExoMars 2020 surface platform to be launched in 2020.
While probing the internal structure of Mars is the primary scientific goal of the "InSight" mission, atmospheric science remains a key science objective. "InSight" will provide a continuous and higher-frequency record of pressure, air temperature and winds at the surface of Mars than previous "in situ" missions.
One of the challenges for a Mars habitat is for it to maintain suitable temperatures in the right places in an habitat. Things like electronics and lights generate heat that rises in the air, even as there are extreme temperature fluctuation outside. There can be large temperature swings on Mars, for example at the equator it may reach 70 degrees F (20 degrees C) in the daytime but then go down to minus 100 degrees F (−73 C) at night.
In the 2016 board game "Terraforming Mars", players are tasked with the terraforming of the planet by increasing oxygen and temperature levels, and by placing oceans on the surface of Mars.
One of the challenges for Mars habitats is maintaining the climate, especially the right temperature in the right places. Things like electronics and lights generate heat that rises in the air, even as there are extreme temperature fluctuation outside.
Gravity on Mars is about 38% that of Earth, allowing Martian lava tubes to be much larger in comparison. Lava tubes represent prime locations for direct observation of pristine bedrock where keys to the geological, paleohydrological, and possible biological history of Mars could be found. The surface of Mars experiences extreme temperature fluctuations and receives a high amount of Ionizing radiation due to the lack of a magnetic field and the planet’s thin atmosphere, which is about 100 times thinner than Earth’s. The thin atmosphere allows Mars to more easily radiate heat energy away, so temperatures near the equator can get up to during a summer day, and then drop down to at night. Subsurface conditions on Mars are dramatically more benign than those on the surface, which lead researchers to believe that if life did (or does) exist on Mars, it would most likely be found in these more hospitable environments. Life forms would not only be protected from the high surface temperatures and ultraviolet radiation, but also from wind storms and regolith dust. Martian lava tubes could possibly trap volatiles such as water which is considered essential for life, and may also contain reservoirs of ancient ice since cold air can pool in lava tubes and temperatures remain stable. The ability to tap into these reservoirs may provide dramatic insight into the paleoclimatology and astrobiological histories of Mars.
The novel series by Kim Stanley Robinson known as the "Mars trilogy" chronicles the colonization and terraforming of Mars. The novels are titled according to the dominant color in the stage of terraforming achieved in each volume: "Red Mars" (1992), when Mars is still in its natural state; "Green Mars" (1993), when plants are able to grow in the atmosphere; and "Blue Mars" (1996), when the atmospheric pressure and temperature have risen high enough for seas and rivers to form.
In 2014, Smith attracted local and eventually national news media attention when he stated during a legislative committee hearing:
As you [Energy and Environment Cabinet official] sit there in your chair with your data, we sit up here in ours with our data and our constituents and stuff behind us. I don't want to get into the debate about climate change, but I will simply point out that I think in academia we all agree that the temperature on Mars is exactly as it is here. Nobody will dispute that. Yet there are no coal mines on Mars. There are no factories on Mars that I'm aware of. Despite Smith's assertion, the average temperature of Mars is colder than that of Earth by 138 degrees Fahrenheit. At the time of the senator's remarks, the Curiosity rover had last reported a high of , low . The temperature in the capital city of Frankfort, Kentucky ranged from to .
The Pathfinder lander recorded the variation of diurnal temperature cycle. It was coldest just before sunrise, about , and warmest just after Mars noon, about . At this location, the highest temperature never reached the freezing point of water (), too cold for pure liquid water to exist on the surface.
The seasonal lag on Mars is no more than a couple of days, due to its lack of large bodies of water and similar factors that would provide a buffering effect. Thus, for temperatures on Mars, "spring" is approximately the mirror image of "summer" and "autumn" is approximately the mirror image of "winter" (if you consider the solstices and equinoxes to be the beginnings of their respective seasons), and if Mars had a circular orbit the maximum and minimum temperatures would occur a couple of days after the summer and winter solstices rather than about one month after as on Earth. The only difference between spring temperatures and summer temperatures is due to the relatively high eccentricity of Mars's orbit: in northern spring Mars is farther from the Sun than during northern summer, and therefore by coincidence spring is slightly cooler than summer and autumn is slightly warmer than winter. However, in the southern hemisphere the opposite is true.
Despite strong evidence for glacial flow on Mars, there is little convincing evidence for landforms carved by glacial erosion, e.g., U-shaped valleys, crag and tail hills, arêtes, drumlins. Such features are abundant in glaciated regions on Earth, so their absence on Mars has proven puzzling. The lack of these landforms is thought to be related to the cold-based nature of the ice in most recent glaciers on Mars. Because the solar insolation reaching the planet, the temperature and density of the atmosphere, and the geothermal heat flux are all lower on Mars than they are on Earth, modelling suggests the temperature of the interface between a glacier and its bed stays below freezing and the ice is literally frozen down to the ground. This prevents it from sliding across the bed, which is thought to inhibit the ice's ability to erode the surface.
The 2001 Mars Odyssey is currently orbiting Mars and taking global atmospheric temperature measurements with the TES instrument. The Mars Reconnaissance Orbiter is currently taking daily weather and climate related observations from orbit. One of its instruments, the Mars climate sounder is specialized for climate observation work. The MSL was launched in November 2011 and landed on Mars on August 6, 2012.[141] Orbiters MAVEN, Mangalyaan, and TGO are currently orbiting Mars and studying its atmosphere.
The Valley of Dor, with the ring of cliffs around it and Sea of Korus within it, is placed in a mile-deep crater at Mars' South Pole. However, Burroughs makes a mistake in that he has the sun rise in the east and set in the west as elsewhere in the planet, and the moons are visible from the Valley. In reality, at the South Pole, Mars' moons would not be seen, and the sun would not rise in the east and set in the west (all directions away from the Pole are "north" in any case), but instead ring the cliffs for half the Martian year, and leave the area shrouded in darkness for the other half of the Martian year. In addition, unlike what one would expect at the south pole of Mars, the temperature in the Valley of Dor is mild and temperate, and although that may be accounted for by its being in a deep crater, the temperature in the Therns' fortress on the surrounding cliffs does not appear to be all that cold either.
Immediately after arriving in Budapest, Milanković met the Director of the Library of the Hungarian Academy of Science, Koloman von Szilly who, as a mathematician, eagerly accepted Milanković and enabled him to work undisturbed in the Academy's library and the Central Meteorological Institute. Milanković spent four years in Budapest, almost the entire war. He used mathematical methods to study the current climate of inner planets of the solar system. In 1916 he published a paper entitled "Investigation of the climate of the planet Mars". Milanković calculated that the average temperature in the lower layers the atmosphere on Mars is and the average surface temperature is . Also, he concluded that: "This large temperature difference between the ground and lower layers of the atmosphere is not unexpected. Great transparency for solar radiation makes that is the climate of Mars very similar to altitudes climate of our Earth." Today it is known that the average temperature is , but that the ground temperatures and air temperatures generally differ. In any case, Milanković theoretically proved that Mars has an extremely harsh climate. In addition to considering Mars, he dealt with the climatic conditions prevailing on Venus and Mercury. His calculations of the temperature conditions on the neighboring Moon are particularly significant. Milanković knew that one day on the Moon lasts 15 Earth days, and this is the amount and length of night. Milanković calculated that the surface temperature on the day side of the moon reaches +100.5 °C. Also, he calculated that the temperature during the early morning on the Moon, or before the rise of the Sun over horizon, was -58 °C. Today it is known that the surface temperature on the day side of the Moon reaches +108 °C and that it falls at night to -153 °C.
The Mars Reconnaissance Orbiter MCS (Mars Climate Sounder) instrument was, upon arrival, able to operate jointly with MGS for a brief period; the less-capable Mars Odyssey THEMIS and Mars Express SPICAM datasets may also be used to span a single, well-calibrated record. While MCS and TES temperatures are generally consistent,[34] investigators report possible cooling below the analytical precision. "After accounting for this modeled cooling, MCS MY 28 temperatures are an average of 0.9 (daytime) and 1.7 K (night-time) cooler than TES MY 24 measurements."[35]
The Martian atmosphere is very thin and composed mainly of carbon dioxide, with some nitrogen and argon. The average surface pressure on Mars is 0.6-0.9 kPa, compared to about 101 kPa for Earth. This results in a much lower atmospheric thermal inertia, and as a consequence Mars is subject to strong thermal tides that can change total atmospheric pressure by up to 10%. The thin atmosphere also increases the variability of the planet's temperature. Martian surface temperatures vary from lows of approximately −140 °C (−220 °F) during the polar winters to highs of up to 20 °C (70 °F) in summers.
Between the Viking and Mars Global Surveyor missions, Mars saw "Much colder (10-20 K) global atmospheric temperatures were observed during the 1997 versus 1977 perihelion periods" and "that the global aphelion atmosphere of Mars is colder, less dusty, and cloudier than indicated by the established Viking climatology," with "generally colder atmospheric temperatures and lower dust loading in recent decades on Mars than during the Viking Mission." The Mars Reconnaissance Orbiter, though spanning a much shorter dataset, shows no warming of planetary average temperature, and a possible cooling. "MCS MY 28 temperatures are an average of 0.9 (daytime) and 1.7 K (night- time) cooler than TES MY 24 measurements." Locally and regionally, however, changes in pits in the layer of frozen carbon dioxide at the Martian south pole observed between 1999 and 2001 suggest the south polar ice cap is shrinking. More recent observations indicate that Mars' south pole is continuing to melt. "It's evaporating right now at a prodigious rate," says Michael Malin, principal investigator for the Mars Orbiter Camera. The pits in the ice are growing by about 3 meters (9.8 ft) per year. Malin states that conditions on Mars are not currently conductive to the formation of new ice. A web site has suggested that this indicates a "climate change in progress" on Mars. Multiple studies suggests this may be a local phenomenon rather than a global one.
Del Mar's climate is considered mediterranean-subtropical with warm, dry summers and mild, humid winters. Temperatures exceed only on a few occasions throughout the year and rarely drop below . The average yearly temperature in Del Mar is approximately .
Examples of Mars surface temperatures:
There can be large temperature swings on Mars; for example, at the equator, daytime temperature may reach in the Martian summer, and drop down to at night. According to a 1958 NASA report, long-term human comfort requires temperatures in the range at 50% humidity.
Mars-1 was the first spacecraft launched to Mars in 1962, but communication was lost while en route to Mars. With Mars-2 and Mars-3 in 1971-1972, information was obtained on the nature of the surface rocks and altitude profiles of the surface density of the soil, its thermal conductivity, and thermal anomalies detected on the surface of Mars. The program found that its northern polar cap has a temperature below -110 °C and that the water vapor content in the atmosphere of Mars is five thousand times less than on Earth. No signs of life were found.
Magnesite was detected in meteorite ALH84001 and on planet Mars itself. Magnesite was identified on Mars using infra-red spectroscopy from satellite orbit. Controversy still exists over the temperature of formation of this magnesite. Low-temperature formation has been suggested for the magnesite from the Mars derived ALH84001 meteorite. The low-temperature formation of magnesite might well be of significance toward large-scale carbon sequestration.
The existence of liquid water on the surface of Mars requires both a warmer and thicker atmosphere. Atmospheric pressure on the present-day Martian surface only exceeds that of the triple point of water (6.11 hPa) in the lowest elevations; at higher elevations water can exist only as a solid or a vapor (assuming pure water). Annual mean temperatures at the surface are currently less than 210 K, significantly less than what is needed to sustain liquid water. However, early in its history Mars may have had conditions more conducive to retaining liquid water at the surface.