2. THE SUN
• Age: 4.6 Billion Years
Mass: 1,989,100,000,000,000,000,000 billion kg (333,060 x Earth)
Surface Temperature: 5500 °C
3. MERCURY
• Mass: 330,104,000,000,000 billion kg (0.055 x Earth
Known Moons: none
Orbit Period: 87.97 Earth days
Surface Temperature: -173 to 427°C
First Record: 14th century BC
Recorded By: Assyrian astronomers
4. VENUS
• Mass: 4,867,320,000,000,000 billion kg (0.815 x Earth)
Known Moons: none
Orbit Period: 224.70 Earth days
Surface Temperature: 462 °C
First Record: 17th century BC
Recorded By: Babylonian astronomers
6. MARS
• Mass: 641,693,000,000,000 billion kg (0.107 x Earth)
Known Moons: 2
Orbit Period: 686.98 Earth days (1.88 Earth years)
Surface Temperature: -87 to -5 °C
First Record: 2nd millennium BC
Recorded By: Egyptian astronomers
7. JUPITER
• Mass: 1,898,130,000,000,000,000 billion kg (317.83 x Earth)
Known Moons: 67
Known Rings: 4
Orbit Period: 4,332.82 Earth days (11.86 Earth years)
Surface Temperature: -108°C
First Record: 7th or 8th century BC
Recorded By: Babylonian astronomers
8. SATURN
• Mass: 568,319,000,000,000,000 billion kg (95.16 x Earth)
Known Moons: 62
Known Rings: 30
Orbit Period: 10,755.70 Earth days (29.45 Earth years)
Surface Temperature: -139 °C
First Record: 8th century BC
Recorded By: Assyrians
9. URANUS
• Mass: 86,810,300,000,000,000 billion kg (14.536 x Earth)
Known Moons: 27
Known Rings: 13
Orbit Period: 30,687.15 Earth days (84.02 Earth years)
Surface Temperature: -197 °C
Discover Date: March 13th 1781
Discovered By: William Herschel
10. NEPTUNE
• Mass: 102,410,000,000,000,000 billion kg (17.15x Earth)
Known Moons: 14
Known Rings: 5
Orbit Period: 60,190.03 Earth days (164.79 Earth years)
Surface Temperature: -201 °C
Discover Date: September 23rd 1846
Discovered By: Urbain Le Verrier & Johann Galle
11. PLUTO
Mass: 13,050,000,000,000 billion kg (0.00218 x Earth)
Known Moons: 5
Orbit Period: 246.04 Earth years
Surface Temperature: -229°C
Discovery Date: 18th February 1930
Discovered By: Clyde W. Tombaugh
