The planet known for its extreme high temperatures is Venus. Venus is the second planet from the Sun and has an average surface temperature of about 465 degrees Celsius (about 869 degrees Fahrenheit). This extreme heat is primarily due to a thick atmosphere composed mainly of carbon dioxide, with clouds of sulfuric acid, which creates a strong greenhouse effect. As a result, Venus retains heat and has little variation in temperature between day and night. Despite its high temperatures and inhospitable conditions, Venus has been a subject of interest for scientists studying planetary atmospheres and climate processes.