Mars is named after the Roman god of war. To the Greeks, Mars was known as Ares. It is named after the god of war because of its red color.
Key Facts and Summary
- Mars is the fourth planet from the Sun and the second smallest planet in the solar system.
- Mars is the most widely searched planet for life and has inspired many works of fiction.
- The first person to use a telescope to observe Mars was Galileo Galilei. He observed the Red Planet in 1610.
- Mars is 227.9 million kilometers/141.6 million miles from the Sun.
- Light from the Sun reaches Mars in about 13 minutes.
- Mars is about twice the size of Earth. Its diameter is 6.779 kilometers / 4.212 miles.
- The mass of Mars is about 10 times that of Earth.
- Mars is the outermost Earth-like planet , beyond the orbit of the Earth. It is 50% further from the sun than Earth.
- Mars has two known natural satellites, Phobos and Deimos.
- Phobos is expected to collide with Mars in the distant future.
- The atmosphere on Mars is very thin and is mainly composed of carbon dioxide , nitrogen and argon.
- The tallest volcano/mountain in the solar system is on Mars. It was named Olympus and it appears to have an altitude of 21 kilometers/13 miles.
- Mars also has the largest canyon in the solar system. It was named Valles Marines. It is 4.000 km / 2.500 miles long and has a depth of 7 km / 4 miles. The Grand Canyon on Earth is only 446 kilometers/226 miles long and only 1.6 kilometers/1 mile deep.
- Mars has no magnetic field, but some areas are highly magnetized.
- The average temperature on Mars is -80 degrees Fahrenheit/-60 degrees Celsius.
- Mars represents masculinity, the symbol of the planet used for the male gender.
Mars is widely known as the Red Planet. Its red appearance is caused by the presence of rusty iron underground. The name of the month March comes from Mars.
Mars is visible to the naked eye, therefore, you can see it without using a telescope or binoculars . The Red Planet is so similar to Earth that scientists are trying to find out if life exists there.
Surface and Structure
In many ways, Mars can be considered a brother to Earth. It has seasons, polar ice caps, volcanoes, canyons and weather. There are many signs of ancient floods on the Red Planet, but now water is mostly found in icy mud and thin clouds.
There is evidence of liquid salt water underground, especially on hillsides. That's probably fine if people go there in the future, but observations continue.
Mars is the seventh largest planet in the solar system and the fourth largest planet from the sun. It has the most diverse and complex terrain of any terrestrial planet except Earth.
On the surface of Mars we find the largest mountain in the solar system. It was named Mount Olympus and is three times larger than Mount Everest, the largest mountain on Earth.
Another great feature of Mars is the Valles Marineris, a network of canyons 4.000 km / 2.485 miles long and 2 to 7 km / 1 to 4 miles high.
Hellas Planitia is a massive crater on Mars created by an ancient impact. Located in the southern hemisphere of the Red Planet, it is more than 6 kilometers/3.7 miles deep and 2.000 kilometers/1.242 miles across.
Oceans and lakes may have existed on Mars long ago, but it seems water only existed for a short time. Some people believe there is water beneath the surface of Mars.
There are many differences between the southern and northern hemispheres of Mars. For example, in the Southern Hemisphere, there are many ancient cratered highlands, similar to those on the Moon.
In the Northern Hemisphere, the plains have undergone changes since the Earth was formed long ago, and this hemisphere also has lower elevations.
Time on Mars
A day on Mars is a little longer than a day on Earth. It lasts approximately 24.6 hours. However, a Martian year, or the time it takes the Red Planet to orbit our sun, lasts about 687 Earth days, nearly twice as long as an Earth year.
Fun Facts
- Mars has seasons, just like Earth, but they last longer. This is because it takes longer to orbit the sun. The length of the seasons varies because Mars has an egg-shaped orbit around the sun.
- The longest season on Mars is spring, which lasts 194 days. Autumn is the shortest, lasting only 142 days.
- Occasionally, the winds on Mars are strong enough to create sandstorms. It will take several months for all the dust to settle, which is a big hurdle for the space probe sent there.
- Mars does not have a ring system like Saturn . However, one of its satellites, Phobos, will crash on Mars in the distant future, which could form a ring system around the red planet.
- Many observations and analyzes have shown that Mars was once very similar to Earth, with water and even entire oceans.
- If you stood on Mars and looked at the Sun, it would appear to be about half the size of what we see on Earth.
- Debris from Mars fell on Earth. Scientists are still studying these materials today.
- If you weigh 100 kilograms on Earth, you would weigh 38 kilograms on Mars because Mars' gravity is only 38% of Earth's.
- About six Mars-sized planets would fit within the size of Earth. However, it would take 7 million Mars-sized planets to fill the size of the Sun.
- A book written by Jonathan Swift mentions two moons of Mars, 151 years before they were actually discovered.
- Some believe that the Valles Marines on Mars were the result of a giant collision.
Size and comparison
Mars is the second largest asteroid in the solar system after Mercury, with a diameter of 6.779 kilometers / 4.212 miles. It is 30% larger than Mercury and nearly twice smaller than Earth and Venus.
Neptune and Uranus have a diameter approximately 7.2 times that of Mars. Saturn, on the other hand, is 17.1 times larger in diameter. But the largest planet in the solar system is Jupiter , whose diameter is more than 20 times that of Mars.
Orbits and Rotations
A day/rotation on Mars is completed in 24.6 hours, while the entire journey around the Sun or a year is completed in 669.6 days.
Mars has a relatively obvious orbital eccentricity, about 0.09. Of the other seven planets in the solar system, only Mercury has a more eccentric orbit. It is known that in the past, Mars' orbit was much more circular. 1.35 million Earth years ago, Mars' eccentricity was about 0.002, much lower than that of Earth today.
It is believed that the closest distance between Earth and Mars will continue to decrease modestly over the next 25.000 years.
Axial Tilt
Mars' axis of rotation is tilted at 25.2 degrees, similar to Earth, which has an axial tilt of 23.4 degrees. It has seasons, although they last longer than on Earth because Mars takes longer to orbit the sun. Due to Mars' elliptical egg-shaped orbit around the Sun, the length of the seasons varies.
Structure
Mars is estimated to have a dense core with a radius between 930-1.300 miles / 1.500-2.100 kilometers. It is mainly composed of iron and nickel, with a sulfur content of about 16-17%. The iron sulfide core is thought to be twice as rich in lighter elements than Earth's core.
The core is surrounded by a silicate mantle that formed many of the tectonic plates and volcanic features on Earth and now appears to be dormant.
In addition to silicon and oxygen, the most abundant elements in the Martian crust are iron, magnesium, aluminum, calcium, and potassium. The average thickness of the crust is estimated to be about 50 kilometers/31 miles, with a maximum thickness of 125 kilometers/78 miles. By comparison, Earth's average crust is about 40 kilometers / 25 miles.
Magnetosphere and Atmosphere
It is estimated that Mars lost its magnetosphere about 4 billion years ago. One possible reason is that numerous asteroid impacts and the solar wind interact directly with the Martian ionosphere, reducing the density of the atmosphere by stripping atoms from the outer layers.
Mars' atmosphere is composed of approximately 96% carbon dioxide, 1.93% argon, and 1.89% nitrogen, with trace amounts of oxygen and water. It's dusty. Methane has also been recently detected in the atmosphere, with values indicating whether the source of the reactive gas that should be present is biotic or abiotic.
Climate
If Mars had an Earth-like orbit, its seasons would be similar to Earth's because its axial tilt is similar to Earth's. Spring in the Northern Hemisphere (autumn in the South) is the longest season, lasting 194 days. Autumn in the Northern Hemisphere (spring in the Southern Hemisphere) is the shortest at 142 days. Northern winter (southern summer) lasts 154 days, while northern summer (southern winter) lasts 178 days.
On average, temperatures on Mars are about -80 degrees Fahrenheit / -60 degrees Celsius. In winter, temperatures near the poles can drop to -195 degrees Fahrenheit/-125 degrees Celsius, and Mars has the largest dust storms in the solar system, with speeds exceeding 160 km/h (100 mph). These can range from storms over a small area to huge storms covering the entire planet. They tend to occur when Mars is closest to the sun, increasing global temperatures.
Surface and Geology
Although it is often referred to as the Red Planet, Mars actually comes in many colors. In surface colors such as brown, gold and tan. Its surface size is the same as that of Earth's dry land combined, although it is twice smaller.
Mars has lots of evidence of a watery past, with ancient networks of river valleys, deltas and lake beds, as well as rocks and minerals on the surface that could only have formed in liquid water. Some features suggest that Mars experienced a massive flood about 3.5 billion years ago.
Hydrology/Topography/Volcanoes
Although liquid water cannot exist on the surface of Mars due to low atmospheric pressure (less than 1% that of Earth), except for short periods of time, the volume of the water ice cap appears to be primarily made of water, with the volume of water ice being sufficient to cover the entire planet's surface to a depth of 11 meters or 36 feet.
There are visible landforms that strongly suggest liquid water was already present on the Earth's surface, such as the hematite condensation (above), or Ma'adim Vallis, a roughly 700 km/430 mile valley thought to have been carved by flowing water long ago.
Near the Arctic Cap is the 81.4 km / 50.6 mi wide Korolev crater, where it was found to be filled with approximately 2.200 cubic kilometers / 530 mi of water ice.
There are two permanent polar ice caps on Mars. During the winter, the poles are in continuous darkness, causing 25-30% of the atmosphere to be deposited as carbon dioxide dry ice sheets.
When they are exposed to sunlight again, the carbon dioxide sublimates, sometimes creating clouds of water ice. The two polar caps are mainly composed of water ice, accounting for about 70%.
The dichotomy of Martian terrain is striking, with the northern plains flattened by lava flows contrasting with the southern highlands, pockmarked by ancient impact craters.
Mars is scarred by many impact craters: a total of 43,000 craters with a diameter of 5 kilometers (3.1 miles) or more have been discovered. The largest of these confirmations is the Hellas impact basin, a light albedo feature clearly visible from Earth.
Olympus Mons is an extinct volcano in the vast highland region of Tharsis, which contains several other large volcanoes. However, Olympus Mons is the largest volcano, in fact it is the largest volcano detected in the entire solar system and is approximately three times as tall as Mount Everest.
The Grand Canyon Valles Marineris, also known as the Agathadaemon in old canal maps, has a length of 4,000 kilometers (2,500 miles) and a depth of up to 7 kilometers (4.3 miles). Valles Marineris is about the length of Europe and stretches to one-fifth of the circumference of Mars. In comparison, the Grand Canyon is only 446 kilometers (277 miles) long and nearly 2 kilometers (1.2 miles) deep. Valles Marineris was formed due to the expansion of the Tharsis region, which caused the crust of the Valles Marineris region to collapse.
It is 10 times longer and 10 times wider than the Grand Canyon. The surface of Mars also has sand, which is composed of basalt , hence its gray color.
When the wind blows, dunes are created, including a series of parallel ridges on the crater floor, also creating horseshoe-shaped dunes. Mars also has dust demons, towering wind vortices like tornadoes. When dust devils blow red dust across gray basalt plains, they can leave intricate and beautiful curls.
Mars actually has avalanches. Cliffs towering above the surface can move away in the spring when carbon dioxide thaws, creating huge cascades of rock and dust.
Satellites
Mars has only 2 known satellites named Phobos and Deimos, named after the horses that pull the Martian chariot of the god of war. They are very small, with Phobos having a diameter of about 25 kilometers or 15.5 miles, while Deimos is only 15 kilometers or 9.3 miles. They look so much like asteroids that they are strongly believed to have been captured by the gravity of Mars in the nearby asteroid belt .
Phobos orbits Mars at just 6.000 kilometers or 3.728 miles, moving so fast in its orbit that its orbit is faster than Mars is rotating. Tides from Mars are also changing its orbit, slowly lowering Phobos closer and closer to the Martian surface. It is believed that in a few million years, Phobos will drop low enough that it will actually enter the atmosphere and impact the surface.
Life on Mars
Throughout most of the 19th millennium, it was believed that life on Mars existed in part due to a mistake. An astronomer believes he has observed straight lines on the surface of Mars.
Many people believe that this could only be the work of intelligent life, as the straight lines resemble canals used for irrigation purposes. However, as more advanced telescopes were built and observations of the Martian surface became more accurate - it was discovered that the straight lines were an optical illusion.
Mars and Venus atmosphere Similarity
If Mars is one of the most hospitable planets, then Venus is one of the most inhospitable planets. However, their atmospheres are similar in one composition - carbon dioxide - which is 95% on Mars and 97% on Venus.
However, the main difference is that Venus's greenhouse effect controls the temperature to around 480 degrees Celsius, while Mars does not exceed 20 degrees Celsius.
Other features
Mars has a thin but active atmosphere. The Red Planet's surface is not active, but its volcanoes are dead. The atmosphere on Mars is composed of carbon dioxide, nitrogen and argon.
The planets closest to Mars, its neighbors, are Earth and Jupiter. Mars also has two moons, Phobos and Deimos. They are smaller than Earth's moon.
Phobos is slowly landing on Mars, and scientists believe it will one day crash on the Red Planet. Mars is the outermost terrestrial planet and is 50% closer to the sun than Earth.
Many missions are being sent to Mars, so many that the red planet is theoretically filled with robots. Some projects on Earth hope to colonize the Red Planet starting in 2022.
