'Cause you're hot then you're cold ⁣ ⁣ The closest planet to the Sun, Mercury’s surface has dramatic temperature shifts. They range from 800°F (430°C) to as low as -290°F (-180°C) due to the planet's lack of atmosphere. Instead of an atmosphere, Mercury has a tenuous exosphere, created from solar winds and meteor strikes, recent strikes appear blue because of freshly churned-up rock from the impacts. ⁣ ⁣ Captured by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft in 2008, this image shows the planet just after the spacecraft made its closest approach to the planet's surface. MESSENGER was the first spacecraft to orbit Mercury, and its primary mission was to study the planet's chemical composition, geology, and magnetic field.⁣ ⁣ Image description: Primarily gray, Mercury appears surrounded by the blackness of space and shrouded in shadow on the left side of the photo. Many craters dot the surface, some with a blue tint.⁣ ⁣ Credit: NASA/Johns Hop...