The layer of gases surrounding a planet is known as the atmosphere. This gaseous layer is essential for supporting life as it provides the necessary conditions for living organisms. The atmosphere plays a crucial role in regulating temperature, protecting against harmful solar radiation, and facilitating weather patterns. Earth's atmosphere is composed mainly of nitrogen, oxygen, and smaller amounts of other gases like carbon dioxide and argon. Other planets in the solar system have different atmospheric compositions, which can affect their surface conditions and potential for hosting life. Understanding planetary atmospheres is vital for both environmental science and space exploration.