Whatever speed an objet may gain while entering orbit should be lost when exiting it, right ?
That is true from the frame of reference of the planet. From the frame of a 3rd distant object that you want to accelerate towards, it appears you have gained momentum.
So I guess it’s the cinetic energy of the planet that is actually fuelling the spacecraft, isn’t it ?
Yes, but the mechanism for ‘extracting’ the kinetic energy from the planet is by using ‘gravity’, hence the name, “Gravitational Slingshot”.
That is true from the frame of reference of the planet. From the frame of a 3rd distant object that you want to accelerate towards, it appears you have gained momentum.
Yes, but the mechanism for ‘extracting’ the kinetic energy from the planet is by using ‘gravity’, hence the name, “Gravitational Slingshot”.