# Calculating Force to Change Earth's Orbit - Kepler

• kepler
In summary, changing the Earth's orbit would require applying a force in the direction of the desired change, either in the same direction or opposite direction of its current motion around the Sun. The force needed would depend on the desired change in the orbit's shape or inclination.

#### kepler

Hi,

If we were to change the Earth's orbit, what force should we apply and in what direction? Shoud we go against G.(M_Earth + M_Sun) / distance^2 or against the centripetal force, M_Earth.v^2/distance?

I've calculated this last one and I got the result:

3,542396634E+22 Newtons

Is this correct?

Regards,

Kepler

The problem with mv^2/r is that you've assumed the Earth is in a circular orbit. It is, in fact, somewhat elliptical. That difference drastically changes the problem.

It really depends on how you want to change the orbit.(what kind of an orbit do you want after the change?) If you want to raise it to an higher orbit, you have to push it in the same direction it is moving around the Sun. If you want to move it into a lower orbit, you push in the opposite direction. If you push directly towards or away from the Sun, you will change the shape of the orbit such that it will be closer to the Sun at part of its orbit and further at another part. If you push it at a right angle to its orbital plane, you will change the inclination or "tilt" of the orbit.

## 1. How is the force to change Earth's orbit calculated?

The force to change Earth's orbit is calculated using Newton's Law of Universal Gravitation. This law states that the force between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.

## 2. What factors affect the force needed to change Earth's orbit?

The force needed to change Earth's orbit is affected by several factors, including the mass of the object exerting the force, the distance between the two objects, and the mass of Earth itself. Other factors such as the angle and direction of the force can also impact the amount of force needed.

## 3. How does Kepler's third law relate to calculating the force to change Earth's orbit?

Kepler's third law, also known as the harmonic law, states that the square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit. This law is essential in calculating the force needed to change Earth's orbit because it provides a relationship between the orbital period, distance, and gravitational force.

## 4. What is the formula for calculating the force to change Earth's orbit?

The formula for calculating the force to change Earth's orbit is F = G * (m1 * m2) / r^2, where F is the force, G is the gravitational constant, m1 and m2 are the masses of the two objects, and r is the distance between them. This formula is derived from Newton's Law of Universal Gravitation.

## 5. How can the force to change Earth's orbit be applied in real-life scenarios?

The force to change Earth's orbit is a crucial factor in understanding and predicting celestial events, such as eclipses and comets. It is also essential in the field of space exploration, as it helps scientists and engineers calculate the necessary force to launch spacecraft and navigate them to different planets and celestial bodies.