Answer: Highly-elliptical-earth-orbit (heo)
Explanation: Highly-elliptical-earth-orbit (heo) satellite system has unique properties
which is used by governments for spying and by scientific agencies for observing celestial bodies. It is an extremely elongated orbit that is useful for communication satellites which creates signals between a source transmitter and a receiver at different locations on earth. They are used by government for spying, scientific agencies for observing celestial bodies, for the internet and telephone communications.
Please check the attached picture
Any ride that oscillates back and forth or moves only in a complete circle utilizes periodic motion.