What the scale shows us depends not only on our mass, but also on the strength of the gravitational field in which we find ourselves. This means that, with the same body, we can weigh more or less depending on whether we are on Earth, on the Moon or on an asteroid. In the most important bodies in the Solar System, a person weighing 70 kg would weigh:
26.4 kg On Mercury
63.4 kg On Venus
11.6 kg On the Moon
26.3 kg On Mars
165.4 kg On Jupiter
64 , 1 kg On Saturn
62.2 kg On Uranus
78.7 kg On Neptune
4.6 kg On Pluto
1,895 kg On the Sun
9,800,000,000,000 kg In a neutron star
Any body attracts what surrounds it
All objects, no matter how minute, attract each other. And yes, there is attraction beyond the emotional between one body and another, but absolutely irrelevant. Within the umbrella of terrestrial gravitation, that powerful gravitational field of the Earth, any other force is totally appeased. If it did not exist, our bodies would have a greater force of attraction on other bodies and on smaller objects.
Without gravity, inertia makes any moving object unstoppable. Once a car was accelerated, its speed would be constant; we would need a system that would put much more braking force on the vehicles to be able to stop them.
To lift any object we need to exert a force similar to its weight. In a zero gravity situation, the mass remains, but the weight does not exist, so we could change the wheels of the car without using a jack.
Our digestive system uses gravity to carry out intestinal transit. Without gravity, the peristaltic movements that push the food down would be much more energetic, something like eating face down.
The most popular sports would also suffer in the absence of gravity. The practice of any sport based on throwing (basketball, soccer, tennis, shooting, golf …) or jumping (horse riding, height, trampoline …) would lose its meaning completely.
11.2km / sg to be able to escape from Earth
If the Earth attracts us with enough intensity that nothing ‘falls’ from it by its own weight, how is it possible to launch ships into space and thus make them escape such magnetism?
The strength of the gravitational field decreases with distance, so that, at a certain altitude, it is possible to reach a point of weightlessness. For this, it is necessary to print the object to be launched with enough speed to originate a centrifugal force whose magnitude balances that of gravity.
The minimum initial velocity that an object needs to escape the gravitation of an astronomical body and continue moving without having to make another propellant effort is called the escape velocity; Its value depends on the mass of said body and the distance between it and the center of the body from which it intends to take off. Earth’s escape velocity has been calculated at about 11.2 km / s.
The system used to propel a rocket is based on the principle that exposes Isaac Newton’s third law of mechanics and that states that every action causes a reaction of equal intensity and opposite direction. The rocket engine releases gases downward that propel the rocket upward with the same force.
Within our immense planetary cage there are possibilities of reaching weightlessness for short periods of time. Astronauts use large pools to rehearse the tasks they will perform in orbit, since the buoyancy simulates the lack of weight quite well, despite the friction with the water. For shorter experiences, cosmonauts travel in planes that trace parabolic paths in the air; for a few seconds, in the vicinity of the apogee of the trajectory, they experience the sensation of weightlessness in a closed receptacle.
To fine-tune the instruments that they will use in space, they also use towers specially designed for it, inside which they are released in free fall.
In everyday life, operating an elevator to go down allows you to feel weightless for a few tenths of a second. And, if we want to experience more adventure, we just have to parachute. In any case, the effects of zero gravity on our body would not be pleasant: bones and muscles atrophy and disoriented blood accumulates freely in different areas of the body.