Mars, better known as “The Red Planet,” is a small rocky planet approximately 50% further away from the sun than Earth. Due to the iron content present on its surface and atmosphere, which rusts away quickly over time and turns it red in appearance.
Mars features two moons named Phobos and Deimos. Additionally, Mars boasts polar ice caps, volcanoes, and canyons that add unique geologic features to its landscape.
1. It has a thick atmosphere
Mars’ atmosphere consists of carbon dioxide with trace amounts of nitrogen and argon, along with dust particles smaller than an eyelash. Scientists can study its atmosphere using spacecraft in orbit, Mars rovers/landers on Earth as well as big telescopes on Earth to study it further. Scientists have documented numerous meteorological and seasonal phenomena on Mars such as clouds forming various shapes, polar ice caps expanding or retreating, dust storms as well as atmospheric thickness sufficient enough for liquid water. Furthermore, scientists believe that once upon time its atmosphere once supported liquid water as well as atmospheric research suggests otherwise.
Each winter on Mars, approximately one third of its atmosphere condenses into polar ice caps at each pole, and during spring up to half of that air re-enters the atmosphere for another season before dissipating again by autumn – leading to fluctuations in surface pressures on Mars and an unpredictable environment.
Scientists don’t fully understand why and how polar caps form and dissipate, though they believe this to be related to changes in atmospheric temperature and winds. Furthermore, scientists are intrigued by how some polar caps contain both freshwater and salty water molecules – they believe these could come about through reactions between underground rock minerals.
Scientists gain further insights into Mars’ past atmosphere through studying oxygen isotopes. Oxygen isotopes are variations of oxygen with different masses, determined by how many neutrons there are in each atom, that remain in the atmosphere longer. Heavier versions can help estimate original atmosphere thickness; in the case of Mars we see that its early atmosphere contained significantly more 18O than Earth did (when measured against 16O).
Mars lacks an ozone layer, meaning ultraviolet radiation from the Sun and other celestial sources can reach its surface without being blocked by oxygen and can damage any organic compounds exposed. But due to its thin atmosphere, which blocks most direct sunlight and lets in only half as much energy, this does not lead to direct damage of organic molecules exposed.
2. It has a huge mountain
Mars may not support life on its surface, but the planet does boast some of the solar system’s largest mountains. Olympus Mons is its tallest dormant volcano and stands nearly three times higher than Earth’s tallest peak – Mount Everest – while Pavonis Mons, Ascraeus Mons and Arsia Mons are other massive mountains found here on Mars. They all exist within Tharsis region which also houses Valles Marineris Canyon as part of Tharsis region which also features powerful volcanoes such as Olympus Mons.
Mars’ enormous mountains exist due to a lack of moving tectonic plates; therefore when volcanic mountains form they can continue to emit lava for an extended period and build massive masses.
These mountains are even more striking because Mars contains only limited areas of flat land; most of its surface consists of mountains and volcanoes with some exceptions in its northern plains, which resemble an eroded coastline and have led some scientists to speculate that such odd features might indicate evidence of former ocean life on Mars.
Mars boasts mountains with both steep and gentle slopes, due to the planet once having an abundant atmosphere that kept its ground warm and allowed for various terrain types to form.
As Mars’ atmosphere began to deplete, its temperature began to decrease and its surface became much more rugged. Over time, Mars lost most of its water and eventually turned red; scientists speculate that primitive life may have existed there early on but would likely have had to survive underground because of harsh environmental conditions.
Mars may lack lakes, but its desert-like features do include sand dunes. Composed of basaltic rock with grey hue, when wind blows it forms patterns such as parallel ridges or horseshoe-shaped dunes. Furthermore, Mars boasts dust devils resembling tornadoes for added flair.
3. It has a blue sky
Mars skies are blue due to the water-ice clouds present there. These tiny particles, responsible for giving Mars its unique color palette, may only be one-tenth the size of Martian dust and about one thousandth thicker than human hair, yet are capable of scattering sunlight to make the sky appear blue – just as Earth skies do too!
At shorter wavelengths of light, Mars’ atmosphere is also more transparent than our own; therefore blue sunlight from the Sun can easily pass through its atmosphere and combine with other colors to produce white light. Red and orange wavelengths however have difficulty passing through and must instead be scattered and filtered before reaching our eyes – leading to bright red sunsets on Mars!
Martian skies are also blue due to the fact that Mars is an extremely cold planet with few greenhouse gases, making it hard for heat from its surface to escape into space and close in temperature all year round, meaning that its surface and atmosphere stay relatively close in temperature all year. Therefore, seasonal changes on Mars are very extreme: during short, warm summers norther half experiences long cold winters as opposed to any equivalency between northern half and souther half.
Planet Earth is also subject to devastating dust storms, with winds reaching very high speeds that send dust flying miles into the atmosphere and for weeks or even months obscuring sunlight from visible space. These massive dust storms may even obstruct Sunlight temporarily!
Mars takes longer to rotate on its axis than Earth due to being further away from the Sun, giving rise to shorter days – 24.6 hours to be exact – than we do here on Earth. Furthermore, two moons – Phobos and Deimos – named for Ares, god of war were discovered only 151 years after Jonathan Swift wrote about them in Gulliver’s Travels!
4. It has a thin atmosphere
Mars is known for its brilliant red hue, yet has an extremely thin atmosphere compared to Earth. Carbon dioxide emissions make up less than one percent of its volume and there is no evidence of tectonic plate movement on Mars, meaning there aren’t volcanoes and canyons like those found here on our home planet.
Mars’ thin atmosphere can be partly explained by its distant orbit around the sun; with half as much sunlight falling on it than on Earth, so temperatures remain lower on Mars than elsewhere on its surface.
Mars lacks oceans, so its weather patterns differ significantly from our own. One major difference is that Mars seasons last longer – spring in the northern hemisphere lasts 194 days while autumn lasts only 142.
One reason is due to Mars not possessing any water-vapor greenhouse effect; without this effect, Mars doesn’t remain warm enough for significant moisture retention in its air. Furthermore, due to Mars’ extremely low density (objects there weigh only one-third as much as on Earth), they move much quicker.
Though it remains uncertain if life ever emerged on Mars, evidence indicates liquid water once flowed on its surface – in particular deltas, river valley networks and dry riverbeds. Furthermore, Mars boasts some of the smoothest regions in its solar system that may have been created through flooding events.
Mars’ thin atmosphere is often disturbed by dust storms that cover its entirety, sometimes lasting months and dislodging red-tinged iron dust found there, dispersed through giant dust devils similar to tornadoes. These storms often displace red dust into space.
Phobos and Deimos, named for the horses that pulled Mars’ chariot, may have once been asteroids before being drawn into orbit by Mars’ gravity.