Astronomy Practice Exam

What is the average temperature on Venus?

1. 500 degrees F

2. 870 degrees F

3. 400 degrees F

4. 300 degrees F

The correct answer is: 870 degrees F

The average temperature on Venus is approximately 870 degrees Fahrenheit. This extreme temperature is primarily due to the planet's thick atmosphere, which is composed mainly of carbon dioxide, with clouds of sulfuric acid. This composition creates a strong greenhouse effect, trapping heat and preventing it from escaping back into space. Venus is often referred to as Earth's "sister planet" due to its similar size and proximity, but its atmospheric conditions lead to surface temperatures that are hotter than those found on Mercury, despite the latter being closer to the Sun. The high average temperature is consistent across the planet, as the dense atmosphere helps distribute heat evenly, resulting in very little variation between day and night temperatures. In contrast, the other options do not accurately represent Venus's conditions and would suggest much cooler temperatures that fail to account for the severe greenhouse effect present on the planet.