Surveying The Solar System

Poking Around the Neighbourhood

What’s Out There?

• What are the celestial bodies?

• How far away are they?

• What does the earth have in common with them?

• How is the Earth different?

We’ve gotten a few answers…

• Hubble

• Space Probes– Venera– Solar Observer– Pioneer– Viking– Voyager– Pathfinder (Mars)– Apollo (manned)

The Sun

• 1.4 Million km in diameter– 1,400,00 km – 1.4 x 106 km

• Composed mostly of hydrogen• Surface constantly churns and writhes• Some areas are cooler - appear darker

– Known as sun spots

• Violent outbursts called solar flares erupt regularly

• Flares make solar wind

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Sun Statistics• Mass (kg) 1.989e+30• Mass (Earth = 1) 332,830• Equatorial radius (km) 695,000 km• Equatorial radius (Earth = 1) 108.97• Mean density (gm/cm^3) 1.410• Rotational period (days) 25-36*• Escape velocity (km/sec) 618.02• Mean surface temperature 6,000°C• Corona Temperature 1,000,000 °C• Internal Temp 15 000

000 °C• Age (billion years) 4.5

Principal chemistry

•Hydrogen 92.1%•Helium 7.8%•Oxygen 0.061%•Carbon 0.030%•Nitrogen 0.0084%•NeonIron 0.0076%•Silicon 0.0037%•Magnesium 0.0031%•Sulfur 0.0024%•All others 0.0015%

The Planets

• There are 9 planets in our solar system• All are quite different from each other• Inner 4 are rocky (M, V, E, M)• Outer 4 are gas giants (J, S, U, N)• Last on - Pluto - just plain weird (P)

• My Vaccuum Exploded Mom it Just

Sucks Up Nothing - Poop!

Scale - using the Earth as 1

• Earth– Diameter -> 12750 km ( 1 ED)– Distance From the Sun -> 149 599 000 km = 1 AU

• Venus– Diameter -> 12000 km (0.95 ED) 12000 / 12750

• Inside the SS we use Astronomical Units• Outside the SS we use light years