25 Unique Facts About Mars: Earth’s Mysterious Cousin

Bearing a similar tilt to Earth – Mars has a 25° tilt while our planet has a 23.5° tilt – Mars also experiences the same four seasons, though they are more extreme.

The red planet’s seasons are much longer than ours. Due to Mars’ elliptical orbit, spring and summer are longer in its northern hemisphere while fall and winter are longer in the southern. They are also more intense with hotter summers and colder winters.

Though the red planet is often cited as a potential second Earth, we would not be able to breathe in its atmosphere made up of 96% carbon dioxide and less than 0.2% oxygen. Earth’s 21% oxygen is right about where we need to be. Scientists are currently testing microbes that can be sent ahead of humans to begin converting and creating oxygen on the planet.

In the last quarter of the 19th century, astronomers generally believed intelligent life was living on Mars. Italian astronomer Giovanni Schiaparelli noticed relatively straight lines on the Martian surface which he and other astronomers of the time believed were irrigation canals constructed by intelligent beings. As telescopes developed in the early 20th century, this assumption was proved wrong – though not before giving birth to plenty of sci-fi about the red planet, including Marvin the Martian.

Mars’ surface is rich in iron, giving it a reddish color. This composition has led to cultures as far back as the Egyptians naming it after the color. The Egyptians named it Her Desher (“the red one”), the Chinese named it “fire star”, and the Romans named it Mars, after their god of war (equivalent to Ares in Greek mythology).

An enormous system of canyons, the Valles Marineris stretches 2,600 miles (4,200 km) across the Martian surface and is up to 4.3 miles (7 km) deep. Placing it on Earth and into context, the Valles Marineris would span from New York to San Francisco and then some.

A Martian year is significantly longer than an Earth year (the time it takes to make one rotation of the sun). On Earth, we have 365 days whereas Mars has 687 days.

The Martian day is also longer, but only slightly. One Earth day is 23 hours and 56 minutes while one Martian day is 24 hours and 40 minutes. When we do land on Mars, it will be an easier transition than if we went to Jupiter (10 hour day) or Venus (2,802 hour day).

The atmosphere on Mars is 100 times less dense than our own, making landing spacecrafts on its surface tricky as the atmosphere does not help as much in slowing down their descent as it does on our blue planet. Despite this lack of density, it is still dense enough to permit weather and winds.

Mars experiences much greater temperature fluctuations than our own planet. Whereas the coldest it has gotten on Earth’s surface is -126° F (-88° C) and the hottest 136° F (58° C), Mars fluctuates between -284° F (-140° C) and 86° F (30° C). The average temperature on each is 57° F (14° C) on Earth and -81° F (-63° C) on Mars. That’s a cold planet!

Martian dust storms are among the fiercest in the solar system and are even the largest. A dust storm can envelop the entire planet and last for many months.

One of the primary goals of NASA’s well-known Curiosity Rover, currently on the Martian surface, has been to plan for a human visit to the planet. Other goals are understanding the climate and geology of the planet and determining if life ever existed on Mars.

The tallest mountain in the solar system, Olympus Mons, is a shield volcano, similar to those in Hawaii and many Pacific islands. It stands at 13.2 miles (21 km) above sea level on the Martian surface. Three times taller than Mount Everest, Olympus Mons’ surface area is the same as the entire U.S. state of Arizona.

The first spacecraft sent to explore Mars was the Soviet Union’s “Mars 1” in 1962. En route, mission controllers lost contact with the vehicle. The first American spacecraft to reach Mars was Mariner 4 in 1964 which sent back the first pictures of the red planet.

Astronomers have known for years that water exists on Mars, locked up in its polar ice caps. However, they’ve recently found dark streaks on the planet which would indicate flowing water. Mars’ temperatures (#16) would mean the water would have to be incredibly salty to keep it in liquid form.

Despite being considerably smaller than Earth – about half of Earth’s diameter and a tenth of its mass – Mars has a land area similar to that on Earth due to our planet’s high amount of water. This would only apply to Mars’ current state since the Martian oceans have dried and frozen up.

Phobos, the larger of the two Martian moons, orbits the planet so quickly it would set twice (in the East) and rise once (in the west) every day.

Deimos, the smaller moon, is so small that an astronaut on Mars would see it as a full moon just about as brightly as we see Venus in our night sky. Scientists are unsure whether both these moons are captured asteroids or true moons.

Volume-wise, Mars is much smaller than Earth. Over six whole Mars’ would be able to pack into our Earth.

Lower gravity on Mars means you would be able to hop around much easier than on Earth. Its 62.5% less gravity means 100 pounds on Earth are equivalent to about 38 pounds on Mars.

The most well-known supporting evidence for life on Mars refers to NASA experiments in 1996 on Martian rocks which landed on Earth. Inside, the scientists found complex organic molecules and fossilized structures which resemble microbes we are familiar with. Though these findings remain controversial, scientists today generally believe life did exist at some point on Mars (and may even still exist today).

Besides our own planet, Mars is the only planet in the solar system to have polar ice caps. The southern ice cap is made of dry ice and is said to resemble freshly-fallen snow.

Mars’ equivalent of the Grand Canyon, the Noctis Labyrinthus (“labyrinth of the night”) is a highly varied area filled with steep-walled valleys and sloping canyons. Trapped between two highly volatile, techtonically-active areas of the planet, the area has been shaped by the stress of heat and water over millions of years.

Human settlements on Mars could be threatened by Mars’ moon Phobos – thankfully not for tens of millions of years though. Each orbit, Phobos is drawn closer to Mars by the planet’s gravity. (It spirals inward at 6 feet (1.8 m) every 100 years.) Many millennia in the future, the moon will likely crash into Mars or break up above the planet’s surface, creating a ring.

In a 2010 speech at Kennedy Space Center, U.S. President Barack Obama called for the Americans to land a manned mission to Mars by the mid-2030’s, making it the most ambitious Mars exploration plan by any country on record.