The answer depends on several factors, ranging from the position of the planets to the technology used to reach the planet. All the planets move, which means there is only one window open in which you could launch a spaceship towards Mars. Mars is the fourth planet from the sun and the second closest to Earth, but the distance between Earth and Mars is constantly changing as they travel around the Sun.
The average distance between Earth and Mars is 225 million km and it travels at an average speed of 86,871 kilometers per hour in its orbit around the Sun. Approximately every two years, Mars and Earth reach their closest point, called ” opposition”, which is the time when our neighboring red planet can be as close as 55,000,000 km from Earth. Precisely because of this closest approach, space agencies take advantage of the open window of this orbital alignment every two years (it happens once every 26 months) to send spacecraft to dusty Mars.
At its farthest point , Mars is 1.6 astronomical units (AU) away from the Sun, while its closest point, perihelion, is 1.38 AU away . An astronomical unit is the equivalent of 150 million km, and the Sun is one astronomical unit away from Earth.
Using current technology
The journey to Mars would take between 150 and 300 days, depending on the speed of the launch, the alignment of Earth and Mars, and the length of the journey the spacecraft takes to reach its target. It also depends on how much fuel you’re willing to burn to get there. If we spend more fuel, as we do here on Earth, we reduce the travel time.
Thus, in general, the trip to Mars takes about seven to nine months and about 480 million kilometers. If you wanted to do a round trip, in total, it would take us about 21 months, since we would have to wait about three months on Mars to make sure that Earth and Mars were in a suitable position to make the trip back to House.
Although the human being has not yet set foot on Mars, it is the most populated planet in our solar system -not counting Earth- if we talk about robots. Over the years, NASA has sent five robotic vehicles, called rovers, to Mars: Sojourner, Spirit, Opportunity, Curiosity, and Perseverance. And China made history in 2021 by being the second country to land on Mars with its Zhurong rover on the surface.
What if we could go faster?
If we could travel at the speed of light, which is about 300,000 kilometers per second in a vacuum, we would reach Mars at its closest possible approach to Earth in just 3.03 minutes, or 182 seconds . Quick, right? Unfortunately, based on our current understanding of physics and the limits of the natural world, we cannot travel at the speed of light.
We would need a type of technology that would allow the real possibility of interstellar travel . There are various studies underway, such as the recently exposed mathematical model that makes a distortion propulsion theoretically feasible that does not contradict Einstein’s theory and could make us travel at speeds greater than the speed of light. It is about the curvature engine (yes, like the one in Star Trek), proposed for the first time by the Mexican astrophysicist Miguel Alcubierre in 1994.
Since no human being has traveled to Mars yet, we don’t have exact numbers on how fast it is possible to go, because you have to keep in mind that you have to slow down as you get closer to the planet. The best estimates are that human missions to Mars take five to 10 months. We will see it as we can consider it an increasingly tangible option.
Reference: NASA SCIENCE MARS / NASA JPL-Caltech/ Alexey Bobrick et al. Introducing physical warp drives, Classical and Quantum Gravity (2021). DOI: 10.1088/1361-6382/abdf6e
