Planet Mars | The Red Planet
Space’s Frontier For Manned Exploration!
Mars is located just beyond Earth making it the 4th planet from the Sun. It is the 2nd smallest planet and was named after the Roman god of war. It has two small moons (Phobos & Deimos) and is often referred to as the “Red Planet” due to its rusty red dust. Mars is a rocky terrestrial planet about 1/6th the size of Earth and most closely resembles Earth. This makes it a favourite target for space probe missions and location to search for extraterrestrial life!
Fast Summary Facts About The Red Planet!
- Name Origin: Named after the Roman god of the war
- Size: Diameter of 6,779 km (4,212 miles)
- Planet Rank: 2nd smallest
- Number of Moons: 2 (Phobos & Deimos)
- Surface Gravity: 0.38 g (62% less than Earth’s gravity!)
- Orbital Radius: 1.5 AU (1.5 times the Earth-Sun distance)
- Orbital Eccentricity: 0.09
- Length of Year: 1.88 years (687 Earth days!)
- Rotational Period: 24 hours 37 minutes
- Axial Tilt: 25.2° (similar to Earth’s)
- Atmosphere: Carbon dioxide, argon & nitrogen
- Surface Temperature: Between -145°C & + 30°C
Cool Fun Facts About The Dry And Dusty Mars!
- Mars is clearly visible in the night sky to the naked eye. Due to the planets reddish colour, the Greeks named the planet Ares, after their god of war. Interestingly, the Romans also named it after their god of war.
- The Red Planet has the second least circular orbit (after Mercury) of the planets, meaning its distance from the Sun varies between 206.7 and 249.2 million kilometres.
- Planet Earth is about 10 times heavier than Mars and twice the diameter. This results in Mars having a much lower gravity – you could lift boulders 3 times bigger on Mars than you could on Earth!
- Mars’ day (known as a ‘sol’) is 37 minutes longer than Earth’s day.
- On account of Mars’ axial tilt being similar to Earth’s, Mars experiences seasons similar to Earth. However, Mars seasons last nearly twice as long as the Martian year is nearly two Earth years long!
- The planets two moons – Phobos and Deimos - are believed to be captured asteroids, although scientists aren’t 100% sure yet.
- Despite being much smaller, Mars has about the same surface area of dry land as Earth! How cool is that?!
- Mars’ is much colder than Earth with an average temperature of -63°C (-81°F) partly because it is further from the Sun so only receives about 43% of the sunlight, but also due to its thin atmosphere.
- The surface of Mars, especially the southern hemisphere, is scarred by impact craters. Over 43,000 craters with a diameter of at least 5 km (3.1 mi) have been counted.
- Mars’ is home to some of the largest geological structures in the solar system! Such as;
- Olympus Mons – the largest mountain/volcano (3 times higher than Mt Everest!)
- The canyon Valles Marineris with a length of 4,000 km (2,500 mi) is equivalent to the length of the United States of America. By comparison, the Grand Canyon is only 446 km (277 mi) long.
- The entire, relatively flat, northern hemisphere of Mars maybe the site of the largest observed impact crater in the solar system!
- Of all the planets and moons in the Solar System, Mars is the most like Earth; albeit a cold, dry and desert-like version. It’s easy to see why Mars is like Earth as it has polar ice caps, seasons, clouds, mini-tornados and dust storms. Billions of years ago, scientists believe it was once a wetter place too, that likely had rivers, lakes and seas!
- Mars actually has the largest dust storms in the solar system, which can grow so large they cover the entire planet!
- Today Mars has a thin atmosphere (Earth’s is 100 times thicker), which is gradually being lost to space, likely leading to the planet becoming a colder, drier and dustier planet.
- Small pieces of Mars’ surface are believed to have arrived on Earth as meteorites after being blasted off the Red Planet & travelling through space for millions of years!
- Mars is the most studied object in the solar system beyond the Moon, as it is seen as one of the most likely locations in the solar system where life either exists or existed in Mars’ early history.
- The most efficient way to travel to Mars is via a 9 month Hohmann transfer orbit. This is the method used by most spacecraft travelling to Mars.
- The Mariner 4 spacecraft made the first flyby of the planet in 1965 before the Viking landers made the first landings in 1976. Since then rovers and other landers such as Phoenix, Sojourner, Spirit, Opportunity, Curiosity and Insight have explored the surface while orbiters like MARVEN, Odyssey and the Mars Reconnaissance Orbiter study the planet from orbit.
- NASA’s next big exploration mission will be the Mars 2020 rover which will look for signs of microbial life directly! Followed by NASA or SpaceX's manned Mars missions! Exciting times ahead for Mars Exploration fans!