Scientists have compiled the most detailed gravitational map of Mars yet. The main problems of flying to Mars (11 photos)
Let's imagine that we are going on a journey through the solar system. What is the gravity on other planets? On which ones will we be lighter than on Earth, and on which ones will we be heavier?
While we have not yet left the Earth, let's do the following experiment: mentally descend to one of the earth's poles, and then imagine that we have been transported to the equator. I wonder if our weight has changed?
It is known that the weight of any body is determined by the force of attraction (gravity). It is directly proportional to the mass of the planet and inversely proportional to the square of its radius (we first learned about this from a school physics textbook). Consequently, if our Earth were strictly spherical, then the weight of each object moving along its surface would remain unchanged.
But the Earth is not a ball. It is flattened at the poles and elongated along the equator. The equatorial radius of the Earth is 21 km longer than the polar radius. It turns out that the force of gravity acts on the equator as if from afar. This is why the weight of the same body is different places The earth is not the same. Objects should be heaviest at the earth's poles and lightest at the equator. Here they become 1/190 lighter than their weight at the poles. Of course, this change in weight can only be detected using a spring scale. A slight decrease in the weight of objects at the equator also occurs due to the centrifugal force arising from the rotation of the Earth. Thus, the weight of an adult arriving from high polar latitudes to the equator will decrease by a total of about 0.5 kg.
Now it is appropriate to ask: how will the weight of a person traveling on planets change? solar system?
Our first space station- Mars. How much will a person weigh on Mars? It is not difficult to make such a calculation. To do this, you need to know the mass and radius of Mars.
As is known, the mass of the “red planet” is 9.31 times less than the mass of the Earth, and its radius is 1.88 times less than the radius of the globe. Therefore, due to the action of the first factor, the gravity on the surface of Mars should be 9.31 times less, and due to the second, 3.53 times greater than ours (1.88 * 1.88 = 3.53 ). Ultimately, it constitutes a little more than 1/3 of the Earth's gravity there (3.53: 9.31 = 0.38). In the same way, you can determine the gravity stress on any celestial body.
Now let’s agree that on Earth an astronaut-traveler weighs exactly 70 kg. Then for other planets we obtain the following weight values (the planets are arranged in ascending order of weight):
Pluto 4.5 Mercury 26.5 Mars 26.5 Saturn 62.7 Uranus 63.4 Venus 63.4 Earth 70.0 Neptune 79.6 Jupiter 161.2
As we can see, the Earth, in terms of gravity tension, ranks intermediate position between the giant planets. On two of them - Saturn and Uranus - the force of gravity is somewhat less than on Earth, and on the other two - Jupiter and Neptune - it is greater. True, for Jupiter and Saturn the weight is given taking into account the action of centrifugal force (they rotate quickly). The latter reduces body weight at the equator by several percent.
It should be noted that for the giant planets the weight values are given at the level of the upper cloud layer, and not at the level of the solid surface, as for the Earth-like planets (Mercury, Venus, Earth, Mars) and Pluto.
On the surface of Venus, a person will be almost 10% lighter than on Earth. But on Mercury and Mars the weight reduction will occur by 2.6 times. As for Pluto, a person on it will be 2.5 times lighter than on the Moon, or 15.5 times lighter than in earthly conditions.
But on the Sun, gravity (attraction) is 28 times stronger than on Earth. Human body would weigh 2 tons there and would be instantly crushed by its own weight. However, before reaching the Sun, everything would turn into hot gas. Another thing is tiny celestial bodies such as the moons of Mars and asteroids. In many of them you can easily resemble... a sparrow!
It is quite clear that a person can travel to other planets only in a special sealed spacesuit equipped with life support devices. The weight of the spacesuit the American astronauts wore on the lunar surface is approximately equal to the weight of an adult. Therefore, the values we have given for the weight of a space traveler on other planets must be at least doubled. Only then will we obtain weight values close to the actual ones.
It's about finances
America has invested approximately $25 billion in lunar program"Apollo" in the 60-70s of the XX century. Those missions that were carried out after Apollo 11 were slightly cheaper. The road to Mars will cost earthlings much more. In order to get to the Red Planet, it is necessary to overcome from 52 to 402 million km. This is due to the peculiarity of the orbit of Mars.
In addition, the mysterious space is full of various dangers. Because of this, there is a need to send several astronauts at once. In this case, the flight of just one person will cost about a billion dollars. In general, the high cost of the flight can be safely included in the list of “Problems of flying to Mars.”
People interacting with space technology and devices have special clothes. It is necessary to protect against microbes that can live in space conditions. A rather complex organism is deinococcus radiodurans, for which 5000 gray of gamma radiation poses no danger. In this case, the death of an adult occurs from five grays. In order to destroy this bacteria, it must be boiled for about 25 minutes.
The habitat of Deinococcus can be almost any place. It's difficult to predict what will happen if a bacterium ends up in space. Perhaps she will become a real disaster. In this regard, there is a heated discussion among critics regarding issues related to the landing of humans on planets where life can exist.
Method of transportation
Today, all space activities are carried out using rockets. The speed required to leave the Earth is 11.2 km/s (or 40,000 km/h). Note that the bullet speed is about 5,000 km/h.
Flying devices sent into space run on fuel, the reserves of which weigh down the rocket many times over. Moreover, this is associated with certain dangers. But in lately The fundamental ineffectiveness of missile devices is of particular concern.
We know only one way of flying - jet. But fuel combustion is not possible without oxygen. Therefore, airplanes are not able to leave the earth's atmosphere.
Scientists are actively searching for alternatives to combustion. It would be great to create anti-gravity!
Claustrophobia
As you know, man is a social being. It is difficult for him to be in a confined space without any communication, as well as to stay for a long time as part of one team. The Apollo astronauts could be in flight for about eight months. This prospect is not tempting for everyone.
It is very important not to let the astronaut feel lonely during space travel. The longest flight was carried out by Valery Polyakov, who was in space for 438 days, more than half of which he arrived there almost completely alone. His only interlocutor was the Space Flight Control Center. Over the entire period, Polyakov carried out 25 scientific experiments.
So long period The astronaut's flight was due to the fact that he wanted to prove that it was possible to carry out long flights and at the same time maintain a normal psyche. True, after Polyakov landed on Earth, experts noted changes in his behavior: the astronaut became more withdrawn and irritable.
I think it’s now clear why the role of psychologists is so important when sending astronauts. Experts select people who can stay in one group for a long period of time. Those who easily find a common language get into space.
Spacesuit
The main task of the spacesuit is to create inside it high blood pressure, since in space conditions a person’s lungs can “explode”, and he himself can swell... All spacesuits provide protection for astronauts from such troubles.
The disadvantage of modern spacesuits is their bulkiness. As the astronauts noted, it was especially inconvenient to move in such a suit on the Moon. It has been observed that moonwalks are easier to perform with the help of jumps. Mars' gravity allows for freer movement. Nevertheless, it is difficult to create similar conditions on Earth in order to carry out unique training.
In order to feel comfortable on Mars, a person needs a more fitting spacesuit, the weight of which will be about two kilograms. It is also necessary to provide a way to cool the suit and solve the problem of discomfort that such clothing creates in the groin for men and in the chest for women.
Martian pathogens
The famous science fiction writer Herbert Wells in his novel “War of the Worlds” said that the Martians were defeated by terrestrial microorganisms. This is exactly the problem we may encounter when we get to Mars.
There are suggestions about the presence of life on the Red Planet. The most simple organisms may in fact prove to be dangerous opponents. We ourselves can suffer from these microbes.
Any pathogen on Mars is capable of killing all life on our planet. In this regard, the astronauts of Apollo 11, 12 and 14 were quarantined for 21 days until it was determined that there was no life on the Moon. True, the Moon does not have an atmosphere, unlike Mars. Astronauts planning a trip to Mars must be placed in long-term quarantine upon returning to Earth.
Artificial gravity
Another problem for astronauts is weightlessness. If we take Earth's gravity as one, then, for example, the gravitational force of Jupiter will be equal to 2.528. In zero gravity, a person gradually loses bone mass, and his muscles begin to atrophy. Therefore, during space flight, astronauts need long-term training. Springy exercise machines can help with this, but not to the extent necessary. As an example artificial gravity centrifugal force can be given. The aircraft must have a huge centrifuge with a rotation ring. Equipping ships with such devices has not yet been carried out, although similar plans exist.
Being in space for 2 months, the astronauts’ body adapts to the conditions of weightlessness, so returning to Earth becomes a test for them: it is even difficult for them to stand for more than five minutes. Imagine the impact an 8-month trip to Mars would have on a person if bone mass decreased at a rate of 1% per month in zero gravity. In addition, on Mars, astronauts will need to perform certain tasks while getting used to specific gravity. Then - the flight back.
One way to create artificial gravity is magnetism. But it also has its drawbacks, since only the legs are magnetized to the surface, while the body remains outside the action of the magnet.
Spacecraft
Currently exists sufficient quantity spacecraft that can safely get to Mars. But we need to take into account the fact that there will be living people in these cars. Aircraft must be spacious and comfortable, because people will stay in them for a long time.
Such ships have not yet been created, but it is quite possible that in 10 years we will be able to develop them and prepare them for flight.
A huge number of small celestial bodies collides with our planet every day. Most of these bodies do not reach the Earth's surface thanks to the atmosphere. The Moon, which does not have an atmosphere, is constantly attacked by all sorts of “garbage,” as its surface eloquently testifies. will not be protected from such an attack and spacecraft who is going on a long journey. You can try to protect aircraft reinforced sheets, but the rocket will add significant weight.
From solar radiation The earth is protected by an electromagnetic field and atmosphere. In space things are different. Cosmonauts' clothing is equipped with visors. There is a constant need to protect the face, as the direct rays of the sun can cause blindness. The Apollo program developed ultraviolet blocking using aluminum, but astronauts on trips to the Moon noted that various flashes of white and blue often occurred.
Scientists have managed to figure out that rays in space are subatomic particles (most often protons) that move at the speed of light. When they enter the ship, they pierce the ship's hull, but no leaks occur due to the size of the particles, which are significantly smaller than the size of an atom.
People have dreamed of traveling to the stars since ancient times, starting from the time when the first astronomers examined other planets of our system and their satellites through primitive telescopes. Many centuries have passed since then, but alas, interplanetary flights, and especially flights to other stars, are still impossible. And the only extraterrestrial object that researchers have visited is the Moon.
We know that Gravity is the force with which the Earth attracts various bodies.
The force of gravity is always directed towards the center of the planet. Gravity imparts acceleration to a body, which is called acceleration free fall and is numerically equal to 9.8 m/s 2. This means that any body, regardless of its mass, in free fall (without air resistance) changes its speed for each second of fall by 9.8 m/s.
Using the formula to find the acceleration of gravity
The mass of the planets M and their radius R are known thanks to astronomical observations and complex calculations.
and G is the gravitational constant (6.6742 10 -11 m 3 s -2 kg -1).
If we apply this formula to calculate gravitational acceleration on the surface of the Earth (mass M = 5.9736 1024 kg, radius R = 6.371 106 m), we get g=6.6742 * 10 *5.9736 / 6.371*6.371 = 9.822 m/s 2
The standard (“normal”) value adopted when constructing systems of units is g = 9.80665 m/s 2 , and in technical calculations they usually take g = 9.81 m/s 2 .
The standard value of g has been defined as the "average" in some sense acceleration due to gravity on Earth, approximately equal to the acceleration due to gravity at latitude 45.5° at sea level.
Due to gravity towards the Earth, water flows in rivers. A man jumps and falls to the Earth because the Earth attracts him. The Earth attracts all bodies to itself: the Moon, the water of the seas and oceans, houses, satellites, etc. Thanks to the force of gravity, the appearance of our planet is constantly changing. Avalanches come down from the mountains, glaciers move, rockfalls occur, rain falls, and rivers flow from the hills to the plains.
All living beings on earth feel its attraction. Plants also “feel” the action and direction of gravity, which is why the main root always grows downward, towards the center of the earth, and the stem always grows upward.
The Earth and all the other planets moving around the Sun are attracted to it and to each other. Not only does the Earth attract bodies to itself, but these bodies also attract the Earth to themselves. They attract each other and all bodies on Earth. For example, the attraction from the Moon causes ebbs and flows of water on Earth, huge masses of which rise in the oceans and seas twice a day to a height of several meters. They attract each other and all bodies on Earth. Therefore, THE MUTUAL ATTRACTION OF ALL BODIES IN THE UNIVERSE IS CALLED UNIVERSAL GRAVITY.
To determine the force of gravity acting on a body of any mass, it is necessary to multiply the acceleration of gravity by the mass of this body.
F = g * m,
where m is the mass of the body, g is the acceleration of free fall.
The formula shows that the value of gravity increases with increasing body weight. It is also clear that the force of gravity also depends on the magnitude of the acceleration of gravity. This means that we conclude: for a body of constant mass, the value of the force of gravity changes with a change in the acceleration of gravity.
Using the formula for finding the acceleration of gravity g=GM/R 2
We can calculate g values on the surface of any planet. The mass of the planets M and their radius R are known thanks to astronomical observations and complex calculations. where G is the gravitational constant (6.6742 10 -11 m 3 s -2 kg -1).
Planets have long been divided by scientists into two groups. The first is the terrestrial planets: Mercury, Venus, Earth, Mars, and more recently Pluto. They are characterized by relatively small sizes, a small number of satellites and a solid state. The remaining ones are Jupiter, Saturn, Uranus, Neptune - giant planets consisting of hydrogen and helium gas. They all move around the Sun in elliptical orbits, deviating from a given trajectory if a neighboring planet passes nearby.
Our “first space station” is Mars. How much will a person weigh on Mars? It is not difficult to make such a calculation. To do this, you need to know the mass and radius of Mars.
As is known, the mass of the “red planet” is 9.31 times less than the mass of the Earth, and its radius is 1.88 times less than the radius of the globe. Therefore, due to the action of the first factor, the gravity on the surface of Mars should be 9.31 times less, and due to the second, 3.53 times greater than ours (1.88 * 1.88 = 3.53 ). Ultimately, it constitutes a little more than 1/3 of the Earth's gravity there (3.53: 9.31 = 0.38). It is 0.38 g from the earth's, which is about half as much. This means that on the red planet you can gallop and jump much higher than on Earth, and all the weights will also weigh much less. In the same way, you can determine the gravity stress on any celestial body.
Now let's determine the gravity stress on the Moon. The mass of the Moon, as we know, is 81 times less than the mass of the Earth. If the Earth had such a small mass, then the gravity force on its surface would be 81 times weaker than it is now. But according to Newton's law, the ball attracts as if all its mass is concentrated in the center. The center of the Earth is located at a distance of the Earth's radius from its surface, the center of the Moon is at a distance of the lunar radius. But the lunar radius is 27/100 of the earth’s, and by decreasing the distance by 100/27 times, the force of attraction increases by (100/27) 2 times. This means that the final gravity stress on the surface of the Moon is
100 2 / 27 2 * 81 = 1 / 6 earthly
It is curious that if water existed on the Moon, a swimmer would feel the same way in a lunar pond as on Earth. Its weight would decrease six times, but the weight of the water it displaced would decrease by the same amount; the ratio between them would be the same as on Earth, and the swimmer would plunge into the water of the Moon exactly the same amount as he dives here.
acceleration of free fall on the surface of some celestial bodies, m/s 2
Sun 273.1
Mercury 3.68-3.74
Venus 8.88
Earth 9.81
Moon 1.62
Ceres 0.27
Mars 3.86
Jupiter 23.95
Saturn 10.44
Uranium 8.86
Neptune 11.09
Pluto 0.61
As can be seen from the table, an almost identical value of the acceleration due to gravity is present on Venus and is 0.906 of the Earth’s.
Now let’s agree that on Earth an astronaut-traveler weighs exactly 70 kg. Then for other planets we obtain the following weight values (the planets are arranged in ascending order of weight):
But on the Sun, gravity (attraction) is 28 times stronger than on Earth. The human body would weigh 20,000 N there and would be instantly crushed by its own weight.
If we have to travel in space through the planets of the solar system, then we need to be prepared for the fact that our weight will change. The force of gravity also has various effects on living beings. Simply put, when other habitable worlds are discovered, we will see that their inhabitants differ greatly from each other depending on the mass of their planets. For example, if the Moon were inhabited, it would be inhabited by very tall and fragile creatures, and vice versa, on a planet with the mass of Jupiter, the inhabitants would be very short, strong and massive. Otherwise, you simply cannot survive on weak limbs in such conditions, no matter how hard you try. The force of gravity will play important role and during the future colonization of the same Mars.
Before the invention of the telescope, only seven planets were known: Mercury, Venus, Mars, Jupiter, Saturn, Earth and Moon. Their number suited many. Therefore, when Galileo’s book “The Starry Messenger” was published in 1610, in which he reported that with the help of his “ telescope“He managed to discover four more celestial bodies, “not seen by anyone from the beginning of the world to the present day” (the satellites of Jupiter), this caused a sensation. Galileo's supporters rejoiced at the new discoveries, while his opponents declared an irreconcilable war on the scientist.
A year later, the book “Reflections on Astronomy, Optics and Physics” was published in Venice, in which the author argued that Galileo was mistaken and the number of planets must necessarily be seven, since, firstly, in Old Testament the seven-branched candlestick is mentioned (which means seven planets), secondly, there are only seven holes in the head, thirdly, there are only seven metals and, fourthly, “the satellites are not visible to simple eye, and therefore cannot influence the Earth, therefore, they are not needed, and therefore they do not exist.”
However, such arguments could not stop the development of science, and now we know for sure that the satellites of Jupiter exist and the number of planets is not at all seven. Nine large planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto, of which only the first two do not have satellites) and over three thousand small planets called asteroids revolve around the Sun.
Satellites orbit around their planets under the influence of their gravitational field. The force of gravity on the surface of each planet can be found using the formula F T = mg, where g = GM/R 2 is the acceleration of gravity on the planet. Substituting the mass M and radius R of different planets into the last formula, we can calculate what the gravitational acceleration g is equal to on each of them. The results of these calculations (in the form of the ratio of the acceleration of gravity on a given planet to the acceleration of gravity on the Earth's surface) are given in Table 7.
From this table it is clear that the greatest acceleration of free fall and, therefore, greatest strength gravity on Jupiter. It is the largest planet in the solar system; its radius is 11 times and its mass is 318 times greater than that of the Earth. The attraction is weakest on distant Pluto. This planet is smaller than the Moon: its radius is only 1150 km, and its mass is 500 times less than that of the Earth!
The small planets of the solar system have even less mass. 98% of these celestial bodies orbit the Sun between the orbits of Mars and Jupiter, forming the so-called asteroid belt. The first and largest asteroid, Ceres, was discovered in 1801. Its radius is about 500 km, and its mass is approximately 1.2 * 10 21 kg (i.e., 5000 times less than that of the Earth). It is easy to calculate that the acceleration of gravity on Ceres is approximately 32 times less than on Earth! The weight of any body turns out to be the same number of times less. Therefore, an astronaut who found himself on Ceres could lift a load weighing 1.5 tons (Fig. 110). 
However, no one has yet been to Ceres. But people have already been to the Moon. This first happened in the summer of 1969, when the Apollo 11 spacecraft delivered to our natural satellite three American astronauts: N. Armstrong, E. Aldrin and M. Collins. “Of course,” Armstrong later said, “in conditions of lunar gravity you want to jump up... Highest height the jump was two meters - Aldrin jumped to the third step of the lunar cabin stairs. Had no falls unpleasant consequences. The speed is so low that there is no reason to fear any injury.”
The acceleration of free fall on the Moon is 6 times less than on Earth. Therefore, when jumping upward, a person rises there to a height 6 times greater than on Earth. To jump 2 meters on the Moon, as Aldrin did, requires the same force as on Earth when jumping 33 cm.
The first astronauts were on the Moon for 21 hours and 36 minutes. On July 21, they launched from the Moon, and on July 24, Apollo 11 splashed down on Pacific Ocean. People left the Moon, but five medals with images of five dead astronauts remained on it. These are Yu. A. Gagarin, V. M. Komarov, V. Grissom, E. White and R Chaffee.
1. List all the major planets that make up the Solar System. 2. What are the names of the largest and the smallest of them? 3. How many times does the weight of a person on Jupiter exceed the weight of the same person on Earth? 4. How many times is the gravity on Mars less than on Earth? 5. What do you know about Ceres? 6. Why did the astronauts on the Moon walk more like jumping than normal walking?
> > > Gravity on Mars
Which gravity on Mars compared to the Earth: description of indicators for the planets of the solar system with photos, impact on the human body, calculation of gravity.
Earth and Mars are similar in many ways. They are virtually convergent in surface area, have polar caps, axial tilt, and seasonal variability. In addition, both show that they have survived climate change.
But they are also different. And one of the most important factors stands gravity. Believe me, if you are going to colonize an alien world, then this moment will play an important role.
Comparison of gravity on Mars and Earth
We know that Earth's conditions helped life form, so we use them as a guide when searching for alien life. Atmospheric pressure on Mars - 7.5 millibars versus 1000 on Earth. The average surface temperature drops to -63°C, and ours is 14°C. The photo shows the structure of Mars.
If the length of a Martian day is almost identical to that of Earth (24 hours and 37 minutes), then the year covers as many as 687 days. Martian gravity is 62% lower than on Earth, that is, 100 kg there turns into 38 kg.
This difference is affected by mass, radius and density. Despite the similarity in surface area, Mars covers only half the Earth's diameter, 15% of the volume and 11% of the massiveness. What about the gravity of Mars?
Calculating Mars' gravity
To determine Martian gravity, the researchers used Newton's theory: gravity is proportional to mass. We are colliding with a spherical body, so gravity will be inversely proportional to the square of the radius. Below is a gravity map of Mars.
The proportions are expressed by the formula g = m/r 2, where g is surface gravity (multiples of Earth = 9.8 m/s²), m is mass (multiple of Earth = 5.976 10 24 kg), and r is radius (multiple of Earth = 6371 km) .
The Martian mass is 6.4171 x 10 23 kg, which is 0.107 times greater than ours. The average radius is 3389.5 km = 0.532 Earth's. Mathematically: 0.107/0.532² = 0.376.
We do not know what will happen to a person if he is immersed in such conditions on long term. But studies of the effects of microgravity show loss muscle mass, bone density, impacts to organs and decreased vision.
Before we go to a planet, we must study its gravity in detail, otherwise the colony is doomed to death.
There are already projects that deal with this issue. So Mars-1 is developing programs to improve muscles. A stay on the ISS longer than 4-6 months shows a loss of muscle mass by 15%.
But the Martian one will take much more time for the flight itself, where the ship is attacked by cosmic rays, and staying on the planet, where there is also no protective magnetic layer. Crew missions of the 2030s It's getting closer, so we must make addressing these issues a priority. Now you know what gravity looks like on Mars.
