A Tour of THE SOLAR SYSTEM

1. A Tour of THE SOLAR SYSTEM

3. The Sun • The Sun is a star. • It is 4,500 million years old • It takes 8 minutes for its light to reach the Earth. • 98.6% mass of the Solar System • Consists of Hydrogen (74%) and Helium (24%) • Radius: 695,000 km • Mass: 333,000 Earths! • Surface Temperature: 5,500 °C • Core Temperature: 15,500,000 °C

6. Mercury • Scans indicate that craters at the poles contain water ice. • Temperatures reach 450°C during the day. At night, the temperature drop to -170°C. • Radius: 2400 km • Mass: 3.30 x 1023 kg • Distance from Sun: 58 million km (0.38 AU)

7. Mercury Earth Size Comparison

8. Venus • Surface temperatures are a constant 500°C due to thick atmosphere • The atmosphere is 95% Carbon Dioxide • Venus rotates in the opposite direction to other planets in the Solar System. • Radius: 6500 km • Mass: 4.86 x 1024 kg • Distance from Sun: 108 million km (0.72 AU)

9. Mountain ranges on Venus taken with Radar. Note the metallic snow. Thick cloud cover blanketing Venus

10. Earth Radius: 6,400 km Mass: 5.8 x 1024 kg Temperature: -80 to 60 °C Distance from Sun: 146 million km (1 AU) Surface is 70% covered by water. Over 2200 manmade satellites in orbit

11. Mars • Surface temperatures are between 0°C and -100°C • Has the highest mountain in the Solar System – the Olympus Mons (24km high and 600km wide at the base) • Radius: 3400 km • Mass: 6.4 x 1023 kg • Distance from Sun: 228 million km (1.5 AU)

13. Size comparison of the Inner Planet

14. Asteroid Belt • Located between Jupiter and Mars • Has a dwarf planet, Ceres – 950km in diameter • Gravity from Jupiter prevented debris from forming into a planet

15. Ceres – the dwarf planet Gaspro – a 400km-long asteroid

16. Jupiter • Made up of 90% hydrogen, 10% helium • probably has a core of rocky material of 10 to 15 Earth-masses • Great Red Spot – a storm that has been raging for over 300 years. As big as 2 Earths. • Has over 63 moons • Radius: 71000 km • Mass: 1.9 x 1027 kg • Distance from Sun: 780 million km (5.2 AU)

18. Time-lapse animation from Voyager I on approach to Jupiter.

19. While Hiding Behind The Sun, Jupiter Loses One Of Its Belts

20. Io – The most volcanically active object in the Solar System Europa – ice-covered moon that may harbour life

21. Saturn • 75% hydrogen, 25% helium with a rocky core and liquid hydrogen mantle. • The rings are 250000km in diameter but only 1 km thick. • Has 34 named moons • Radius: 60000 km • Mass: 5.7 x 1026 kg • Distance from Sun: 1400 million km (9.5 AU)

22. Saturn’s Rings showing spoke formations Mimas – a small moon of Saturn

23. Uranus • Composed mainly of rock and various ices • Has a tilt of 97° so rotates on its side • has 21 named moons and 6 unnamed • Surface temperature of ~50K (-223°C) • Radius: 25000 km • Mass: 8.7 x 1025 kg • Distance from Sun: 2900 million km (19.2 AU)

24. Neptune • The existence of Neptune was predicted as it was noticed that Uranus’ orbit did not fit with Newton’s laws - another planet must be influencing Uranus' orbit. • Discovered in 1846 • September 2011 marks one orbit since it was discovered. • Radius: 25000 km • Mass: 1 x 1026 kg • Distance from Sun: 4500 million km (30 AU)

25. Neptune showing its horizontal axis and ring formations

26. Clouds high in the atmosphere of Neptune

27. Pluto • Downgraded from ‘planet’ to ‘dwarf planet’ in 2006 • Smaller than The Moon • Has one moon - Charon

29. Kuiper Belt • 30 to 55 AU • Like the asteroid belt but consisting of debris made of ices

30. Oort Cloud • Hypothetical source of comets that stray into our Solar System • 50,000 AU from the Sun

31. The Milky Way