Much of the work of getting a spacecraft to its destination is done before it is launched. All objects in the solar system are constantly moving. Scientists must know the clockwork of the solar system well enough to predict where a spacecraft's destination will be, when to launch and how fast to go to meet it in space. In addition to the movement of the objects in the solar system, scientists must take gravity in account. Gravity exerted by large bodies like planets and the Sun in the solar system will "bend" the flight of a spacecraft. If a flight is planned carefully, a spacecraft can use the gravity of planets and moons to do a swingby or be pulled into orbit.
Much of the "aiming" of spacecraft is done at or near launch, when the huge launch vehicle that puts it into space can push it onto a course that will take it to the right place. Once a spacecraft is in flight, small course corrections can be performed.
Ask any question below to learn about how spacecraft travel through space.
How can a spaceship leave orbit?
How do we put a spacecraft into orbit?
How do we know the location of spacecraft?
Do small errors in space navigation matter?
How did DS1 get into space?
How does gravity work in space?
How do objects in space travel?
How does NASA run space missions?
What are different kinds of orbits?
Why is it a good idea to launch a ship into orbit from near the equator?
What is a flyby?
How is NASA overseeing the DS1 mission?
How do spacecraft use an orbit to move from planet to planet?
How can we use planets and moons to slingshopt a space ship into a different path?