A communications satellite is an artificial satellite that relays and amplifies radio telecommunications signals via a transponder.

Coordinated Universal Time (UTC) is the primary time standard by which the world regulates clocks and time.

Cosmology is the scientific study of the universe as a whole, including its origin, evolution, and ultimate fate.

"Cosmos" is a Wikipedia page that serves as an overview of the vast and complex subject of the cosmos, also known as the universe.

Earth is the third planet from the Sun in our solar system and the only known celestial body to support life.

The electromagnetic spectrum is the range of frequencies of electromagnetic radiation and their corresponding wavelengths and energies.

Helium is a chemical element with the symbol He and atomic number 2.

Liquid helium is a physical state of helium at very low temperatures at standard atmospheric pressures.