Mars experiences temperatures as low as -140deg C in its winters; during its summers however, temperatures can reach +20degC.
Humans looking to explore Mars will have to adapt to its extreme temperatures, but finding water may prove even harder.
Temperature
Mars, as the fourth planet from the sun, is much colder than Earth due to its distance from the sun and thin atmosphere, which make retaining heat energy difficult. Temperatures on Mars range significantly, reaching up to 70F during summer at its equator and as low as -225degF near its poles during wintertime.
Mars’ thin atmosphere is also less dense than Earth, meaning its surface responds quickly to variations in solar radiation, leading to diurnal and semidiurnal tides, producing winds across its surface, which are stronger than gravitational tides caused by changes in sea level.
Mars experiences seasons similar to Earth, yet always remains much colder. Spring on Mars lasts 194 sols while autumn lasts 142 sols; their duration depends on how tilted Mars’ rotation axis tilts during its orbit around the sun; as one hemisphere faces towards more sunlight at certain points during each year.
Scientists have determined that the atmosphere of Mars consists of 95% carbon dioxide. This gas is responsible for its extremely thin atmosphere – only around one twentieth the density of our own. This difference in atmospheric pressure explains why Martian weather responds so swiftly.
Additionally, Mars’ atmosphere possesses lower thermal inertia than Earth, meaning that when sunlight shines on it it heats up much quicker and results in dramatic fluctuations between daytime and nighttime temperatures.
Mars’ low temperatures make it unlikely for human life to exist on its surface, though some organisms known as cryophiles could survive there with temperatures between -4degF and 68degF if temperatures were warmer. Such organisms must, however, be protected against radiation to survive in any case.
Humidity
Mars’ atmosphere consists of mostly carbon dioxide and very little water, meaning that its surface remains cold despite being farther away from the sun than Earth and receiving less direct sunlight than we do here on Earth. Due to these characteristics, living conditions on Mars are extremely harsh compared to Earth, making the planet hard for human habitation.
Mars’ surface is covered by a thin layer of dust and particulates known as regolith, comprised largely of silicates and rock particles. This porous regolith may hold water vapor, liquid water or even frozen frost that will typically vanish as temperatures warm during the day. It isn’t unusual for rovers to witness frost on Mars’ surface, although any frost formed will usually dissipate as temperatures warm.
At night, temperatures on Mars drop drastically at the poles – reaching as low as -73 degrees Celsius! At the equator temperatures usually peak around 20 degrees Celsius during summer days but can drop significantly overnight. One Martian year lasts 687 Earth days long, and two-times longer seasons than our own Earthly ones exist: summer, autumn, winter, and spring (SAMWP).
Finding water on our planet may not be impossible, but finding pure liquid water would likely not be sustainable due to temperature variations on Earth that prevent reaching its boiling point – this makes bulk form water unlikely and instead may exist as salt solutions or brine solutions instead.
The Mars Science Laboratory (MSL) rover features a relative humidity sensor, a small instrument used to measure how much water there is in the atmosphere. Additionally, this instrument measures temperature on Mars’ ground and atmosphere as well as UV radiation at its surface – this information is then transmitted back home each day so scientists can better understand weather patterns on Mars.
Water may have contributed to past climate shifts on Mars. Scientists are still investigating how and when these occurred; their answer likely involves factors such as global climate change, greenhouse gas emissions and composition of its atmosphere.
Clouds
Mars’ atmosphere is generally extremely thin and clouds are scarce; however, dust storms may stir up enough fine particles that mesospheric clouds form; these look similar to Earth’s noctilucent or night-glowing clouds and usually form high up at about 80 km (50 mi).
Clouds may consist of either water or carbon dioxide. When Mars’ atmospheric temperatures dip to very low levels, condensing of water molecules within clouds occurs and can illuminate dark skies with scattered sunlight from above. At such times, carbon dioxide forms ice crystals which then scatter sunlight back onto Earth as illuminated stars scatter back light from space illuminating dark skies with illuminated stars; such shimmering cloud cover gives scientists clues to its composition.
NASA is inviting members of the public to participate in a new project aimed at helping detect clouds on Mars as part of an effort to understand why its atmosphere has depleted over time. They hope that using data collected, they will be able to better comprehend why Mars has lost so much atmosphere over time.
Curiosity’s observation has revealed unseasonally early, “unusual” clouds made of carbon dioxide ice high in the atmosphere – these so-called nacreous clouds have an iridescent sheen and mother-of-pearl color to them; they form when sunlight hits ice crystals reflecting off them during dawn and dusk on Mars.
Nacreous clouds form in the same region of Mars’ atmosphere where mesospheric clouds usually do, helping connect three major climate cycles: those for water ice, CO2, and dust. Furthermore, these clouds provide insight into Mars’ orbital tilt – its angle relative to the Sun which changes over time – giving valuable clues as to its depth of atmosphere in years past compared with now; had Mars had different orbital tilt, it may have had thicker atmospheric layers; over time though this loss of energy might explain why its current thick atmosphere no longer exists today.
Water
At one point in time, Mars boasted a vast ocean of liquid water covering much of its surface. Due to different conditions on Mars, however, this water eventually moved underground or into its atmosphere and eventually vanished entirely from its surface – though scientists continue to discover evidence that indicates such presence on its surface.
Scientists have detected signs of water in Martian soil, including an unusual mineral called gypsum that was only created when present water existed. Furthermore, scientists discovered that its atmosphere contains water vapor. Furthermore, rocks on its surface contain salts similar to those found in liquid water bodies on earth – though given Mars’ cold temperatures, liquid water may never survive long on its surface.
Reason being, Mars lies closer to the Sun than Earth and cannot retain heat as effectively; consequently, its thin atmosphere cannot contain enough warmth for its surface to remain comfortable during daylight and freeze at nighttime. This results in its surface becoming scorched by sunlight then quickly freezing overnight.
In its earlier history, Earth-like life may have thrived here on our planet. Unfortunately, due to erosion, space radiation, and changes in climate conditions, most of its original water was lost through erosion, and subsequent climate shifts; any remaining moisture now forms polar ice caps and groundwater deposits beneath its surface.
Air and cloudborne moisture contribute a small amount of liquid water, but they cannot support life on Earth. Scientists are searching for evidence of past liquid water on both its surface and deep within our planet – looking specifically at locations with steep slopes where water would flow, as these spots should contain hydrous minerals formed when this flowed over rocks forming hydrous mineral deposits – known as hydrous minerals.
Researchers are exploring the chemical composition of water on Mars to better understand its history, using samples collected from meteorites as well as data gathered by rovers and orbiters to analyse data about relative concentrations of isotopes – in other words, how much hydrogen compared with deuterium can be found present – by studying samples collected from meteorites as well as data collected by rovers and orbiters. Hydrogen and deuterium ratios on Earth tend to be evenly balanced whereas on Mars this ratio is six times greater – but