Mars is 200 million kilometers from Earth

Musk has announced his plan to emigrate to Mars, and the first tourists will go there without return.

Even so, a lot of people are signing up. They don't care if they come back to Earth. They just want to set foot on Mars.

Man has successfully landed on the moon, but all this time has passed without ever landing on Mars?

The reason is that Mars is not as far away from the Earth as the moon. And landing on Mars is hundreds of times more difficult than landing a man on the moon.

So suppose humans send a rocket for a manned mission to Mars, how long would it take to get there?

What risks and challenges do astronauts face during this process?

Let's take a look at how hard it is for astronauts to get to Mars before launch, during flight, and when they land.

A long preparation

Sending a spacecraft to Mars will definitely require a launch vehicle, but the biggest problem right now is that there is no suitable launch vehicle.

We all know that when astronauts enter space, they need to prepare all the things they need in advance, such as food, water and all kinds of daily necessities.

Generally speaking, astronauts do not spend more than half a year on missions in space, and even if they work on the space station for a long time, there are supplies on the way.

The much-anticipated Apollo 11 landing on the moon lasted only about three days, and the astronauts didn't need a lot of supplies.

The Moon is about 380,000 kilometers away from the Earth, but Mars is about 200 million kilometers away on average. Even if humans were to pick the time when they were closest to each other, that would be about 55 million kilometers.

Take the Curiosity rover, which launched in November 2011 and landed on the surface of Mars in August 2012. It took about nine months to get there.

And the Curiosity rover never came back, if we count astronauts going back and forth, that's 18 months, that's a year and a half.

The astronauts need to carry several tons of food alone, or more than 10 tons if daily necessities are included.

That's a huge amount of cargo for a launch vehicle, not to mention if there's room to put supplies on it.

In addition, a year and a half would require a lot of fuel, so if we calculate that, all the launch vehicles we have now are not up to par.

That's why some scientists say that if astronauts want to land on Mars, we need to change the way we think about delivery.

Take the way of refueling, in order to reduce the weight of the rocket transport, so that the right carrier rocket can be found to launch the spacecraft.

So instead of putting all of our supplies on one rocket at the beginning, we would launch three rockets in parallel, one for people, one for supplies, and one for fuel.

So far, humans have not carried out such a plan, but we do not rule out the future for Mars landing.

A hard journey

Even if people could overcome the transport of supplies, the journey to Mars would be extremely difficult for astronauts.

First of all, the astronauts need to stay in the capsule for 18 months. The capsule is narrow and sealed. Staying in such a space for a long time is a very severe test for the astronauts' bodies.

Once a Soviet cosmonaut returned from 311 days in space, pale and drenched in sweat, and described by rescuers as soft as a ball of flour.

That's because the longer astronauts spend in space, the more weightlessness causes muscle atrophy and bone loss.

Secondly, the long journey is also a kind of psychological torture for the astronauts.

The astronauts would have to live in an airtight environment for a year and a half and eat food that wasn't fresh, but specialized space food.

According to the astronauts, space food is not a tasty food, its main purpose is to provide energy, taste is not its goal.

In the absence of gravity, astronauts' sense of taste will be affected, so when astronauts eat space food, they will taste like chewing wax.

Finally, because of the long and long travel times, the chances of encountering danger during the journey are greatly increased.

If they collide with stray objects in the universe, such as meteorites and comets, they will cause very serious injuries to astronauts.

To land on Mars

If humans overcome the long journey to orbit Mars and land on the red planet, the mission will not be complete.

The environment on the surface of Mars is very harsh. It has no atmosphere to protect it, so the whole planet is completely exposed to the sun's radiation.

Astronauts have to wear very heavy spacesuits to protect their bodies from radiation.

The acceleration of gravity on the surface of Mars is 40 percent of that on Earth, and once you reach the surface of Mars, you need time to adjust to the gravity environment.

There's still no evidence of life on Mars, but that doesn't mean that Mars is completely devoid of life, because what we've explored so far is so small.

What would happen if we landed in a place where there was Martian life, and it followed us into the capsule and then back to Earth?

Human dare not imagine, because space life has always been the existence of human fear.

As a Mars explorer, astronauts will surely be collecting soil samples from the Martian surface, just as they did from the lunar soil.

If this sample, if it happens to contain some creatures, they followed humans to Earth, and they mutated and became alien creatures.

Or it could infect humans and cause an unprecedented disease, which would not be as easy as science fiction movies make it out to be, but a matter of human existence.

In general, going to Mars is fraught with dangers, both in terms of pre-launch supplies and the long journey, both physically and mentally demanding.

And all kinds of uncertainties after landing on Mars, these are the problems that humanity needs to solve.

Unfortunately, humans can't solve it right now, so our exploration of Mars is just going to have to stay and send a rover up there.

Some people wonder why humans go to all the trouble to get to Mars if it takes so much effort to land there and the planet itself is not very habitable.

What it means to land on Mars

Humans want to migrate to Mars, not because of its excellent environment or its irreplaceable status, but rather as a novice village where they can practice the skills that future interstellar immigrants will need to master.

In terms of hardware, Mars is indeed inhospitable to life.

First of all, it is so cold that the average temperature is around -60 ° C, with the coldest poles being -80 ° C, and even the equator, where the sun is directly shining, is only 20 ° C during the hottest part of the day.

But as far as the sun goes, Mars has the best environment outside of Earth.

Mercury is so close to the sun, and it doesn't have an atmosphere, that it's over 400 degrees Celsius when it's facing the sun, and minus 170 degrees Celsius when it's facing away.

The temperature difference is too great for human migration.

Venus is closest to Earth in size and mass and has a thick atmosphere, but its atmosphere is carbon dioxide.

So Venus has a very serious greenhouse effect, plus it has a very dense atmosphere with 92 times the pressure of the Earth, and you can't stand on it without crushing it.

Jupiter, Saturn, Uranus, and Neptune are all gas stars, and they don't even have a chance to land on land.

After picking and choosing, only Mars is left as a candidate for emigration.

It's just that Mars doesn't have an ecosystem of its own, so the first thing for humans to do when they get there is to recreate the ecology and build a closed base for humans to live in.

But the failure of our current efforts to simulate the biosphere suggests that we cannot replicate the Earth once we leave it.

For the first batch of passengers to Mars, Musk will say there is no return this sentence, because at the current level of human space, it is really only able to send people there and can not pick them up, become a one-way ticket.

It's a foregone conclusion for the participants, and we can't imagine what they will experience when they live their last moments on Mars. This may be the most important step ever taken by mankind!