If walking along the equator, astronauts need to cross 21.400 km to complete one full circle around Mars and it takes 4.290 hours if traveling continuously.
Simulation of an astronaut observing on Mars. Image: dottedhippo/iStock
Humans have long been interested in Mars and NASA also has ambitious plans to send astronauts to this planet in the next few decades. Since Mars has no ocean or other bodies of water on its surface, could astronauts walk around the red planet? How long would such a trip take?
“Basically, we would need two parameters,” said Erdal Yigit, an associate professor of astrophysics at George Mason University who specializes in planetary atmospheres. These two parameters are the astronaut's velocity (speed and direction) and the distance traveled.
If traveling along the Martian equator, astronauts need to travel 21.400 km to complete one full circle around the planet. The journey across the poles will shorten the journey by 160 miles, but the extreme cold will be a bigger challenge than the harsh conditions on the rest of Mars, according to Yigit.
The astronaut's speed will be about 5 km/h. This is also the average walking speed on Earth, along the equator. Although Mars' gravity is only about 40% of Earth's gravity, Yigit doesn't think walking speed on the red planet will be much different. Like any hiker, astronauts need to carry a large amount of supplies such as oxygen, water, and food, and must wear heavy spacesuits.
If the astronaut walked continuously around Mars at the above speed, the calculation would be very simple, just divide the distance by the speed. The result is about 4.290 hours. A day on Mars, called a sol, consists of about 24,7 hours. Thus, it takes about 174 sols to continuously walk around the red planet, equivalent to more than 1/4 of a Martian year (a Martian year consists of 668,6 sols).
But of course, no one can walk continuously, no matter the planet. Even though carrying enough oxygen, water, food and being able to eat and drink while walking, astronauts still have to stop to sleep. If you sleep about 8 hours per night, the trip needs to add about 56 sols. If the astronaut stops for 4 or 5 hours each sol to eat, rest, change clothes, shower, set up and demolish camp, it will take another 30 - 35 sols.
Thus, a more realistic estimate is that the trip will last at least 265 sols, about 40% of a Martian year. However, this estimate does not take into account other obstacles, such as rough terrain. Mars has many mountains, some taller than any on Earth, as well as valleys, craters, and many other difficult geological formations.
A walk around Mars will not happen in the near future. Humans have walked around the Earth, of course it is impossible to actually walk all the way because of the oceans separating them. But humans have only walked on a small part of the Moon even though they have been to this celestial body many times. Walking too far and too long on Mars will also pose many logistical problems, such as carrying enough food, water, oxygen and withstanding radiation.
Yigit said it's highly unlikely humans will circumnavigate the entirety of Mars, but sending astronauts to the Martian surface still offers many benefits compared to rovers. According to him, the exploration robot is susceptible to dust and has electrical problems. But for astronauts, even when problems arise, they can still find solutions.
Thu Thao (Follow Space)
