Hello everyone!

Today, why not to make a post about rocket science, so lets do it!
Rockets are fundamentally preety simple.. they have an engine, then huge fuel tanks, and last and least, the cabin. The cabin can contain humans, robots, even animals. Rockets are preety simple, because the only thing they need to do is push "up". What is up in this case tho? Well, aginst gravity. Gravity is a very simple force that pushes you to everything thats heavy, well, it doesn't have to be heavy, but it has to have some mass. In fact, my atoms have almost the same force to you as the same amount of atoms inside earth. Why don't I pull you towards me then? Well I do, but you are (propably)very far away from me, and the force from me is so low compared to entire earth, its barley noticable.

The first(and sometimes last) step for a rocket is to get to an orbit. Orbit is simply a point where is close to no air and a point where the rocket continously orbits around the planet. How does that work tho? Well, the planet pulls you into it, but you have so much force that you are "falling" towards the planet in continous circle. This works on earth too, but on much lower distances because of air preassure. If we were in orbit and you would throw a football there, it would also orbit for, well, preety much forever. However theres still some air molecules around earth wherever is the gravity strong enough to hold it, so the ball would eventually slow down and burn in the atmosphere.

What to do now? Well, lets say you're trying to get to moon. First we need to get from earths orbit to moons orbit, and we can do that simply by going to the closest point of our orbit to earth, by just waiting, because thats where our rocket has the best efficiency, and accelerating enough to reach the moons orbit using some simple math. After we have done this burn, we will wait until we reach once agin, the closest point, but to the moon this time. Then, we can slow down, by burning in the opposite direction when we were accelerating.
After we slow down, we are in moons orbit! Now, we can simply slow down enough to reach earths surface, and done, we landed on the moon!

And, how do we define a rocket? Well it can be defined by the amount of payload(stuff) it can carry not counting the fuel, cost and deltaV. What is deltaV(dV for short) exactly? Its simply a unit of how many kilometers/s of acceleration can the rocket accelerate based on the fuel. Why don't we just use the amount of fuel to determine this tho? Well, its because the more fuel your rocket has, the more fuel it needs to lift up itself, because remember, fuel weights something and in this case alot. dV is preety hard to calculate however, so its better to let some proffesional do it for you.

Well, thats about it for today!