The escape velocity of Earth is the minimum velocity an object needs to achieve in order to escape the gravitational pull of the planet and not fall back. It is calculated based on the mass and radius of the Earth.
In reality, the presence of other planets or stars doesn't directly affect the escape velocity of Earth, as the escape velocity is determined solely by the mass and radius of the planet itself. The presence of other celestial bodies can indirectly affect the trajectory of an object in space, but it doesn't change the concept of escape velocity.
The escape velocity from Earth's surface, assuming no atmospheric drag, is approximately 11.2 kilometers per second (or about 6.95 miles per second). If an object is launched from Earth's surface with a velocity equal to or greater than the escape velocity, it will have enough kinetic energy to overcome Earth's gravitational pull and move away indefinitely.
However, it's important to note that in the absence of other gravitational influences, the object's motion would be governed solely by the gravitational pull of Earth. It would follow a hyperbolic trajectory, slowing down as it moves away from Earth due to the gravitational attraction. In theory, it would never come to a complete stop and start falling back, but its velocity would continuously decrease as it moves farther from Earth.
Therefore, even if an object achieves escape velocity from Earth, the gravitational pull of the planet would eventually cause it to slow down and come to a halt at an infinite distance. In practice, however, other celestial bodies, such as the Moon, the Sun, and other planets, significantly affect the motion of objects in space and can alter their trajectories.