Name the first man-made object to reach another world.
Luna -2 became the first man-made object which reached another world, when it crashed on the Moon on 14 September 1959.
Has any spacecraft left the Solar System?
On 2 March 1972, the spacecraft Pioneer-10 was launched with a mission to leave the Solar System and travel for at least two million years. It will never come back.
What is meant by docking of spacecraft?
Docking means linking of spacecraft in space. The spacecraft have to be specially designed for docking, with access doors, tiny rockets for steering and alignment, and clamps to keep the spacecraft locked together after the docking.