We are in an era of renewed interest in Mars. The ambitions of NASA and Elon Musk to put humans on the planet for the first time have generated a great deal of interest in the planet which has interested us for centuries.
This article aims to give you all the facts you need to know about Mars including its size, climate, potential for life and details of missions there from Earth.
Where is Mars?
- Mars is part of our Solar System – it orbits the same sun as Earth.
- The distance between Mars and Earth is between 34 million miles and 249 million miles, depending on their respective orbits. They are at their closest point about every two years with the average distance between them 140 million miles (225 million km).
- Mars is sometimes the closest planet to Earth, but this varies with orbits and generally Venus is the closer.
- Mars is the fourth planet from the Sun, between Earth and Jupiter.
- Mars is on average 41.6 million miles (227.9 million km) from the sun.
What’s it like on Mars?
- Temperature: Being further from the sun, Mars is on average colder than Earth. The surface temperature of Mars can be as low as minus 225 degrees Fahrenheit (minus 153 degrees Celsius) or as high as 70 degrees Fahrenheit (20 degrees Celsius). This varies between day and night and among seasons.
- Weather & seasons: Mars has extreme seasons because of its oval-shaped orbital path around the Sun. At the closest point to the Sun, Mars’s southern hemisphere has a short, hot summer, while the northern hemisphere has a brief, cold winter. At its farthest point from the Sun, the northern hemisphere has a long, mild summer, while the southern hemisphere endures a lengthy, cold winter. Mars also has the largest dust storms in the solar system that can last for months and cover the entire planet.
- Air: The Martian atmosphere is 100 times less dense than Earth and is mostly carbon dioxide. This air is not breathable to humans.
- Terrain: Mars has many features similar to Earth: polar ice caps, volcanoes, deserts, and canyons. Mars is home to the tallest known mountain in the solar system, Olympus Mons, which is 21 km high and 600 km in diameter.
- Time: A year on Mars is 687 days and each day lasts 40 minutes more than one on Earth.
- Water: Mars has water in the form of ice and this has been known since its polar ice caps were discovered by William Herschel in the 17th century. The atmospheric pressure on the surface means that standing bodies cannot exist (they would freeze or vaporize) but in 2015 NASA declared possible evidence of flowing salty water. There is also evidence that Mars had large amounts of water, including oceans, a long time ago when its atmospheric conditions were different.
- Gravity: Mars’ surface gravity is only 37% of the Earth’s. This means you would only weigh 37% of what you would on Earth, and can jump nearly three times higher on Mars.
What is Mars made of?
- Like Earth, Mars has a crust, a mantle and a core that are made up of iron and silicate.
Why is Mars the “Red Planet”?
- Mars has a red appearance because its soil contains iron oxide which gives off this color.
How was Mars named?
- The Romans named Mars after their god of war and we use this name today in English.
- Other languages use different names, for example in Chinese it is called HuoXing, which translates as “fire star” – a reference to its red appearance.
Is there life on Mars?
- There is a possibility of life on Mars. The recent evidence of water would add to the chances of microorganisms being able to survive there. NASA is actively searching for evidence of life or past life on Mars with its Curiosity Rover.
- If true that large bodies of water previously existed on Mars then the chances of life there were much higher.
Does Mars have moons?
- Mars has two moons Phobos and Deimos. They were discovered in 1877 by the American astronomer Asaph Hall.
- They are named after the horses that pulled the chariot of the Greek god of war, Ares. Phobos means “fear” and Deimos means “panic”.
- They are small when compared to the Earth’s moon. Phobos has a diameter of 13.8 miles (22.2 km), and Deimos 7.8 miles (12.6 km).
- Phobos is slowly moving towards Mars. It will crash into Mars or break apart in about 50 million years and may result in a ring of rubble around the planet.
How big is Mars?
- Mars is the second smallest planet in the solar system (the smallest is Mercury).
- The diameter of Mars is 4220 miles (6792 km). That means that Mars is twice as big as the moon, but about half the size of Earth.
- Mars is less dense than Earth, with about 11% of Earth’s mass (this is why gravity is so much lower).
- Mars’ radius is 3,389.5 km
- Mars’ surface area is 144,798,500 km2
How old is Mars?
- Mars is about 4.5 billion years old (similar to Earth).
How can I see Mars?
- Mars can be seen with the naked eye. It can be distinguished by its reddish color.
- It can, of course, be seen in greater detail with a telescope (see the best telescopes for beginners)
When was Mars discovered and who discovered it?
- It is very hard to say who first “discovered” Mars as it can be seen with the naked eye. Howeve,r the ancient Egyptian astronomers were the first to record observations of Mars in 1534 BC.
- Galileo Galilei was the first to observe Mars with a telescope in 1609.
Missions to Mars
- There have been 44 attempted missions to Mars to date. Of these, 21 have been judged as successes (or partial successes). This includes spacecraft doing flybys, orbiting or landing.
- Countries that have attempted missions to Mars are the USA, USSR/Russia, Japan, China and India. The European Space Agency (representing 22 European countries) has also sent missions to Mars.
- The first attempted missions to Mars were by the USSR in 1960, but these were not successful.
- As of 2016, Mars has six functioning spacecraft in orbit and two on the surface.
- NASA’s Mars Curiosity Rover is a car-sized vehicle currently exploring Mars. It landed on Mars in August 2012. Images and other information from the Curiosity Rover can be found on a dedicated NASA webpage.
How long does it take to get to Mars?
- How long it takes to reach Mars depends on where in their orbits the two planets lie when a mission is launched and the technology at the time of launch.
- Viking 1, the first U.S. craft to land on Mars in 1975 took 304 days to get there.
- NASA’s Curiosity Rover took 254 days to get there in 2011.
- Flyby missions have done the journey much more quickly, with the quickest being 128 days.
When will humans visit Mars?
- No human missions to Mars have been attempted to date, although plans to do so date back to the 1950’s.
- There are currently a number of planned missions to take humans to Mars, including Space X’s Interplanetary Transport System that plans to take 100 to the planet.
- NASA is also working towards establishing a human presence on Mars in the coming decades.
Check out these resources for more information about Mars: