"A scientific satellite or probe carries instruments to obtain data on magnetic fields, space radiation, Earth and its atmosphere, the Sun or other stars, planets and their moons, and other astronomical objects and phenomena." (Encyclopædia Britannica, Inc., 2019)


"Spaceflight". Encyclopædia Britannica, Encyclopædia Britannica, Inc. Last modified January 22, 2019.
Accessed February 14, 2019.