Venus is similar to Earth in many ways. The orbit of Venus is closer to that of Earth than any other planet, and it has a similar size and composition. However, the surface characteristics differ greatly.

A year on Venus is equal to 225 Earth days, compared to Earth’s 365-day year. Venus, however, rotates on its polar axis backwards compared to Earth, so a Venus sunrise occurs in the west and sunset is in the east. Furthermore, a Venusian day is 243 Earth days long, which makes it even longer than a Venusian year.

The surface conditions of Venus are far different from that of our own planet. It is blanketed by a thick atmosphere nearly one hundred times denser than ours, and it is made mostly of carbon dioxide, along with some nitrogen and trace amounts of water vapor, acids, and heavy metals. Venus’s clouds are laced with poisonous sulfur dioxide, and its surface temperature is a brutal 900 degrees Fahrenheit (500 degrees Celsius). Interestingly, this is even hotter than Mercury, which is much closer to the Sun. These hostile conditions came about because of a runaway greenhouse effect on Venus that persists to this day.