Regarding to distance to Sun - with increasing order - Mercury, Venus, Earth and Mars are the inner four planets of the solar system.
Firstly, Mercury holds the title of being the nearest to Sun with the distance of 58 million kilometers. Diameter of Mercury is 4,840 kilometers.
The second nearest planet to Sun is Venus which continues to circulate on its path which has a radius of 108 million kilometers. Venus has 12,400 kilometers diameter.
Third nearest planet is our planet Earth which spins 149 million kilometers away from the sun with its diameter of 12,757 kilometers. Unlike the other three inner planets, the Earth is accompanied by a Moon which is 384,400 kilometers away from the Earth and has the diameter of 3,476 kilometers.
The fourth nearest planet is the Mars which is 228 million kilometers away from the Sun and has the diamater of 6,800 kilometers.
To conclude, the inner four planets of the solar system can be sorted in a descending order regarding to diamater sizes as the Earth, the Venus, the Mars and the Mercury.
