Source: https://nssdc.gsfc.nasa.gov/planetary/factsheet/planet_table_british.html Mercury: Diameter (miles: 3032) Length of day (hours: 4222.6) Number of moons: 0 Venus: Diameter: 7521 Length of day: 2802 Number of moons: 0 Earth: Diameter: 7926 Length of day: 24 Number of moons: 1 Mars: Diameter: 4221 Length of day: 24.7 Number of moons: 2 Jupiter: Diameter: 88,846 Length of day: 9.9 Number of moons: 95 Saturn: Diameter: 74,897 Length of day: 10.7 Number of moons: 146 Uranus: Diameter: 31,763 Length of day: 17.2 Number of moons: 28 Nepture: Diameter: 30,775 Length of day: 16.1 Number of moons: 16