Geographical Issues in "Mars Rescue"

during a human mission to Mars, astronaut mark wotte (Matt Damon Matt Damon) lost contact with his crew after a bad storm, and everyone thought he was killed in this mission. However, Mark was lucky to survive, but he found himself alone on a different planet. Faced with the lack of life supplies, Mark must use his intelligence and indomitable spirit to survive and find a way to send a distress signal to the earth that he is still alive, and people on the earth are also faced with the disagreement whether to go to Mars to save him.

Let's talk about

1. Mars

Mars is one of the eight planets in the solar system, with the astronomical symbol ♂. It is the fourth planet in the solar system from the inside out, belonging to the earth-like planet, with a diameter of about 53% of that of the earth, and its rotation period from axial inclination is close to that of the earth, and its revolution time is about twice that of the earth. The orange appearance is hematite (iron oxide) on the surface. In ancient books in China, Mars was called "flicker", while in ancient western countries (ancient Rome) it was called "Mars mythology, the God of War".

Mars is basically a desert planet, with sand dunes and gravel all over the surface and no stable liquid water body (not long ago, NASA announced that there is a small amount of water on Mars). The atmosphere dominated by carbon dioxide is thin and cold, and dust is suspended in it, and dust storms often occur every year. The polar cap composed of water ice and dry ice at both poles of Mars will rise and fall with the seasons.

Compared with the Earth, the geological activities of Mars are relatively inactive, and most of the surface landforms were formed in an active period in ancient times, with dense craters, volcanoes and canyons, including Olympus Mons, the highest mountain in the solar system, and Mariner Canyon, the largest canyon. Another unique topographical feature is the obvious difference between the northern and southern hemispheres: the south is an ancient highland full of craters, while the north is a younger plain.

2. Martian dust storm

The dust storm on the surface of Mars is a unique phenomenon in the atmosphere of Mars, and the whole Mars is shrouded in flying wild sand for a quarter of the year. Because of the high iron content in the Martian soil, the Martian dust storm is stained with orange color, and the air is full of red dust, which looks like an orange cloud from the earth.

After the formation of a global dust storm, the heating effect of the sun on the surface of Mars began to weaken, the temperature difference on Mars decreased, and the dust gradually subsided and fell back to the surface, thus ending a dust storm that lasted for several months. Big storms can sometimes sweep the whole planet.

Martian dust storm is a unique phenomenon in the atmosphere of Mars, which occurs around the perihelion of Mars' orbit. Scientists believe that this is because the sun has a great heating effect on the surface of Mars at this time, hot air rises, dust rises, dust storms begin to form and slowly expand.

3. Martian atmosphere

The atmospheric density of Mars is only about 1% of that of the Earth, and it is very dry with a low temperature. The average surface temperature is-55℃, and water and carbon dioxide are easily frozen. In the early days of Mars, it was very similar to the Earth. Like the earth, almost all the carbon dioxide on Mars is converted into carbonaceous rocks. However, due to the lack of plate movement of the earth, Mars can't recycle carbon dioxide into its atmosphere again, thus it can't produce a significant greenhouse effect. Therefore, even if it is pulled to the same distance from the sun as the earth, the temperature on the surface of Mars is still much colder than that on the earth.

The poles of Mars are permanently covered with solid carbon dioxide (dry ice). The structure of this ice cover is layered, which is formed by alternately overlapping ice layers and changing carbon dioxide layers. In the summer in the north, carbon dioxide is completely sublimated, leaving the remaining ice water layer. Since the carbon dioxide in the south has never completely disappeared, we can't know whether there is an ice layer under the ice in the south (left). The reason for this phenomenon is unknown, but it may be caused by the long-term change of the angle between the equatorial plane of Mars and its orbit, which leads to the climate change. Perhaps there is water deeper under the surface of Mars. This change in the polar cover caused by seasonal changes has changed the pressure of Mars by about 25%. (measured by the Viking). However, the observation through Hubble telescope shows that the environment of Viking at that time was not typical. The atmosphere of Mars seems colder and drier than that detected by Viking.

4. Mars Day

refers to a "day and night" time on Mars, that is, a solar day on Mars. The average length of a sidereal day on Mars is 24 hours, 37 minutes and 22.663 seconds, while the average length of a solar day on Mars is 88775.2449 seconds or 24 hours, 39 minutes and 35.2449 seconds [7]. The average solar day on Mars is only nearly 2.7% longer than that on Earth.

Mars, like the Earth, has a mean time difference, which can be calculated by the daily track of Mars. Because the orbital eccentricity of Mars is larger than that of the Earth, the solar day length of Mars is quite unstable. The average length of a day varies much more than that of the earth. On Mars, the sun sometimes runs 5 minutes slower than the Martian clock, and sometimes it can run 4 minutes faster.

5. Geomorphology of Mars

Like the earth, Mars has diverse landforms, including mountains, plains and canyons. Mars is basically a desert planet with sand dunes and gravel all over the surface. Due to the small gravity and other factors, the terrain size is different from that of the earth. There is a sharp contrast between the topography of the northern and southern hemispheres: the north is a low plain filled with lava, while the south is an ancient highland full of craters, and the two are separated by obvious slopes; Volcanic terrain is interspersed among them, and many canyons are also distributed all over the world. There are polar crowns composed of dry ice and water ice in the north and south poles, and aeolian sand dunes are also widely distributed throughout the planet.

The volcanoes on Mars are different from those on Earth. Except for the low gravity, the mountains can grow very high, and there is no obvious plate movement, so the distribution of volcanoes is mainly hot spots, unlike the structure of fire rings on Earth. Mars volcanoes are mainly distributed in Hutart's Sisi Plateau, Elysium region and scattered in the southern plateau, such as Tyrrhena Patera in the northeast of the Greek plain.

6. Potatoes on Mars

In the movie "Mars Rescue", the hero was trapped on Mars. In order to fill his stomach and survive, he had to use feces as fertilizer and grow potatoes as food, and then he struggled on Mars for 5 days before waiting for rescue. Now, NASA really wants to grow potatoes on Mars, with the goal of setting up a planting base on Mars in the future.

NASA and CIP will start to cultivate potatoes in an environment similar to Mars on earth, hoping to eventually build a climate-controlled "dome" on Mars to grow this ancient crop. The team will replicate the atmospheric conditions of Mars in the laboratory, using soil from the de la Jolla desert in pampas, which is said to be almost identical to the soil found on Mars.

CIP explained: "The atmosphere of Mars is 95% carbon dioxide. High concentration of carbon dioxide will be beneficial to the growth of potatoes, and its harvest will be two to four times that of normal earth environment. If successful, CIP and NASA will become pioneers in future space agriculture. "

why do you choose to grow potatoes? Agronomists have been promoting the benefits of growing potatoes, because potatoes are not only rich in dietary fiber and nutrition, but also can grow in harsh conditions. The earliest record of potato cultivation can be traced back to 25 BC. At present, many countries in the world regard potatoes as the staple food. For example, the per capita annual consumption of European countries is stable at 5-6 kg, and that of Russia is more than 17 kg.

Is it really feasible to grow potatoes on Mars with a minimum temperature of-153℃, no water, inappropriate soil composition and no oxygen? In fact, NASA has simulated the soil and air environment of Mars in the laboratory and successfully planted more than ten kinds of plants.

7. Ice on Mars

In March 27, NASA claimed that if all the ice in the Antarctic crown melted, it could cover the whole planet.

? It is inferred that a larger amount of water is frozen in the thick cryosphere, which can only be released when the volcano is active. The biggest time in history was when the Sailor Valley was formed, a large amount of water was released, resulting in floods that carved out many valley landforms and flowed into the Chris Plain. Another smaller time, when the Cerberus Fossae was formed five million years ago, the released water formed an ice sea in Elysium Planitia, and traces can still be seen today.

The water was taken in Mars Rescue:

The first step is to take out hydrazine, a rocket fuel, and then use it under the catalysis of iridium to decompose hydrazine into. Then, guide hydrogen to a space to ignite, and then water will be generated. N2H4+O2 → N2+2H2O, which is the reaction formula of the whole process.

on September 29th, 215, NASA said that the latest evidence showed that the mysterious dark stripes previously observed on some craters on the surface of Mars may be related to the intermittent appearance of liquid water bodies. The data from satellites show that these dark stripes on the pit wall may be the result of the deposition process of saline water. The key point is that this saline water will be able to change the freezing point and boiling point of water on the surface of Mars, thus making it possible for liquid water to exist on the surface of Mars.

8. What does the Mars rescue want to tell us?

The significance of "Mars Rescue" goes far beyond making FOSS rich in the 2th century. It will rekindle the human desire to explore space and inspire the birth of a new generation of astronauts. Watching Damon's space monologue is a pleasure. Under his interpretation, the miracle of the protagonist Mark's survival on Mars is very convincing.

Let's take a look at Mark's last words:

If I die, I need you to visit my parents.

Although I know it's hard, it's hard for you to talk to an elderly parent about his son who died on Mars.

I didn't give up. I worked hard every day.

please tell them that I love my job.

and my sacrifice is for great things, beautiful things that may change mankind.

the rest, you can read it yourself.