Earth is more suitable because it has an atmosphere that is suitable for life, Earth has fresh water, and it is the safest distance from the sun. Plants increase the viability of life by producing Oxygen for animals and using carbon dioxide for photosynthesis. Volcanoes are present because of the pressure built up in the core of these planets. The inner planets are small in size compared to the outer planets. The temperature is much hotter and they are solid structures. Beyond Mars, these planets are gases and are much larger. There are many pictures and telescopes that explore the universe and show evidence of planets outside of the solar system.
