1 Answers
Discovery and exploration of the Solar System is observation, visitation, and increase in knowledge and understanding of Earth's "cosmic neighborhood". This includes the Sun, Earth and the Moon, the major planets Mercury, Venus, Mars, Jupiter, Saturn, Uranus, and Neptune, their satellites, as well as smaller bodies including comets, asteroids, and dust.
In ancient and medieval times, only the Sun, Moon, five classical planets and comets were visible to the naked eye, along with phenomena now known to take place in Earth's atmosphere, like meteors and aurora. Ancient astronomers were able to make geometric observations with various instruments. The collection of precise observations in the early modern period and the invention of the telescope helped determine the overall structure of the solar system and discover new planets and asteroids. Telescopic observations resulted in the discovery of more planets and asteroids and moons, and determination of the distances to some other stars. The composition of stars and planets was investigated with spectroscopy. Observations of Solar System bodies with other types of electromagnetic radiation became possible with radio astronomy, infrared astronomy, ultraviolet astronomy, X-ray astronomy, and gamma-ray astronomy.
Robotic space probes, the Apollo program landings of humans on the Moon, and space telescopes have vastly increased human knowledge about atmospheric, geologic, and electromagnetic phenomena on other planets, giving rise to the new field of planetary science.
The Solar System is one of many planetary systems in the galaxy. The planetary system that contains Earth is named the "Solar" System because the local star, the Sun, is named Sol, after the Latin word for Sun, "solis". Anything related to the Sun is called "solar"; for example, stellar wind from the Sun is called solar wind.