Answer :
Final answer:
An orbiter is a spacecraft that is sent into orbit around a celestial body to study it from a distance, while an impactor is a spacecraft that is crashed into a celestial body to gather scientific data. A lander is a spacecraft that is designed to safely land on the surface of a celestial body, and a rover is a robotic vehicle that moves on the surface of a celestial body to collect data.
Explanation:
An orbiter is a type of spacecraft that is sent into orbit around a celestial body, such as a planet or moon, to study it from a distance. It typically carries instruments to collect data and transmit it back to Earth. For example, the Mars Global Surveyor orbiter was sent to Mars to obtain high-resolution photography of its surface.
An impactor is a spacecraft or probe that is purposefully crashed into a celestial body to gather scientific data. The impact creates a plume of material that can be studied and analyzed. For instance, the Deep Impact mission sent an impactor to collide with a comet to examine its composition.
A lander is a spacecraft that is designed to land safely on the surface of a celestial body, such as a planet or moon. It is equipped with instruments and sensors to conduct scientific experiments and collect data directly from the surface. The Pathfinder mission landed a rover on the Martian surface to explore and study its geology.
A rover is a robotic vehicle that is designed to move around on the surface of a celestial body. It is equipped with various instruments and cameras to collect data and take images. The Apollo missions to the Moon used rovers to explore the lunar surface and conduct experiments.