Mercury: It’s Hot and It’s Cold

Throughout 2015, we’ll be exploring the Solar System. In January, we visited the Sun. Today, we begin our exploration of the planet Mercury.

Let’s start with a few basic facts that pretty much everyone knows. Mercury is the smallest planet in the Solar System (unless you insist on calling Pluto a planet). Mercury is the planet closest to the Sun. Mercury is one of the coldest places in the Solar System.

Wait… coldest?

While it’s true that the dayside of Mercury is scorching hot (800 degrees Fahrenheit), the temperature on the night side can drop as low as -300 degrees Fahrenheit. The reason for this enormous temperature discrepancy is Mercury’s atmosphere, or rather Mercury’s lack of an atmosphere.

Atmospheres enable planets to trap and redistribute heat, maintaining a relatively constant global temperature. So planets without atmospheres (like Mercury) cook on one side and freeze on the other.

This is just one of many reasons why nobody wants to live on Mercury.

Links

How Hot is Mercury? from Space.com.

What is the Hottest Planet in the Solar System? from Universe Today.