Earth vs Mars - How Do They Compare - Space / Planet Comparison
For as long as humans existed, the planet Mars has always been an object of fascination. Man has often dreamed about what could be lurking on Mars, or if it is even able to sustain life. We thought it would be fun to compare our own planet to the Red Planet in this episode of The Infographics Show, Earth vs Mars. As is commonly known, Mars is named after a mythological figure - the Roman god of war, also known by his Greek name, Ares. In addition to its official name, Mars is sometimes called the Red Planet because of the brownish-red color of its surface, whereas Earth is mostly blue and green.
Mars is a little further away from the sun than Earth is, with Earth being 93 million miles away and Mars being 141 million miles away. It is also half the size of earth, with a diameter of 4,220 miles compared to earth’s 7,926, though it does have the same amount of land mass, due to the earth’s oceans.
The speed at which Earth orbits the sun is 18.5 miles per second. If one was travelling at that speed from New York to Los Angeles, it would take approximately 2 min and 12 seconds, barely enough time to stow your tables and turn off your electronic devices. Mars orbits the sun at the speed of 14.5 miles per second, so that same trip from NY to LA would take a little over 3 minutes.
Because Mars moves slower than Earth and is further away from the sun, a year on Mars is 687 Earth days long compared to Earth’s 365.25 days. Due to Mars’ slower rotation, however, a day is 24 hours and 37 minutes long, compared to Earth’s 23 hours and 56 minutes.
Mars and Earth have very similar tilts (earth: 23.5 degrees, Mars 25 degrees), which means that both Earth and Mars experience winter, spring, summer and fall. Because Mars is further from the sun, however, it is much colder than Earth. The average temperature on Earth is 57 degrees F, while Mars’ is -81 degrees F. On average, Mars is colder than the Antarctic and dryer than the Sahara.
As far as gravity is concerned, Mars has 63% less of it than Earth. This means that you will weigh 63% less on Mars; a 120 lbs woman on Earth would weigh 44.4 lbs on Mars. This also means that if you can jump 2 feet on Earth, you could jump 3.4 feet on Mars, assuming you aren't in heels.
Humans could not survive breathing in Mars’ atmosphere, which is 100 times thinner than that of Earth. While Earth’s atmosphere is a whopping 77% nitrogen and 21% oxygen (with a measly .038% Carbon Dioxide), Mars’ atmosphere is only 0.15% Oxygen and 96% Carbon Dioxide. With such a thin atmosphere, the resulting atmospheric pressure on Mars is only about 1% of that found at sea level on Earth. This is the equivalent pressure found at 22 miles above the Earth’s surface.
(Earth; Nitrogen (77%), Oxygen (21%), Argon (1%), Carbon dioxide (0.038%) MARS: 96% carbon dioxide <2% Argon, <2% Nitrogen, <1% other)
The tallest mountain on Mars is a shield volcano called Olympus Mons, which is more than twice the height of Mount Everest. Scientists have found a lot of recent evidence of volcanic lava which suggests Olympus Mons may still be active. It is the second highest mountain in the entire solar system, topped only by the Rheasilvia central peak on the asteroid Vesta, which is 14 miles high.
The radiation level of Earth is drastically different from that of Mars. While Earth is protected from most radiation from space because of its strong magnetic field, Mars has no such field. The Mars rover Curiosity has enabled us to calculate an average dose of radiation over its 180-day journey: it is approximately 300 mSv, the equivalent of 24 CAT scans. By contrast, a person living next to Fukushima’s damaged nuclear reactor received a radiation dose of 68 mSv.
In terms of moons, Earth only has one, named Luna by the Romans, whereas Mars has two, named Phobos and Deimos. Both moons were discovered in 1877 and are named after the mythological figures of Phobos (or fear) and Deimos (or dread). In Greek mythology, Phobos and Deimos often accompany their father Ares, the god of war, into battle. Phobos is a doomed moon because it is spiraling inward at a rate of 1.8 centimeters per year, and within 50 million years, it will either collide with its parent planet or be torn into rubble and scattered as a ring around Mars.
For much of the 19th century, it was believed life existed on Mars. After a false observation of straight lines that appeared to be canals constructed for irrigation purposes, some scientists concluded that they could only be the work of intelligent life. The development of more powerful telescopes in the early Twentieth century determined that these straight lines were merely an optical illusion. As of now, no definitive evidence for biosignatures or organics of Martian origin has been identified. Life on Earth, on the other hand, is believed to be about 4 billion years old.
At this point, some of you might be wondering how humans would fare on Mars. Because Mars has only 0.6% of Earth's atmospheric pressure, as far as humans are concerned, the planet might as well be a vacuum. After around 15 seconds on Mars, the human body would use up all of its oxygen and it would lose consciousness. The moisture lining in the lungs, as well as the saliva in the mouth, would boil, in effect rupturing the lungs. Any chance of humans living on Mars would obviously require a dramatic terra-formation of the planet. We hope you enjoyed this brief comparison of Earth and Mars. Do you think that humans will ever be able to live on Mars, and if so would you go? Let us know in the comments!