The planet known for its extreme greenhouse effect is Venus. Despite being second from the Sun, Venus has surface temperatures reaching about 900 degrees Fahrenheit (475 degrees Celsius), making it hotter than Mercury. Its thick atmosphere is primarily composed of carbon dioxide, with clouds of sulfuric acid, which trap heat efficiently. This extreme greenhouse effect creates a pressure about 92 times that of Earth at sea level. Surface conditions on Venus are inhospitable, with high temperatures and corrosive atmospheres, making it a challenging location for exploration and study.