- Closest planet to the sun
- Smallest planet in the solar system
- Can only be viewed from Earth in the morning or evening twilight
- Surface is similar to the Moon in appearance, heavily cratered with areas of smooth plains
- Has a large iron core that generates a magnetic field about 1% as strong as Earth’s
- Temperatures range from -300 F to 800 F (bottoms of craters near the poles are the coldest, subsolar point is the hottest)
- Consists of approximately 70% metallic and 30% silicate material