1. Venus

2. Facts Sidereal Day- 117 Solar day 243 days Year- 225 Days
Diameter- 12,100 km (Earth 12,700km)
Mass- .85 mass of Earth
Distance form the Sun .72 AU
Atmosphere- 96% Carbon Dioxide, Nitrogen, small amounts of water vapor
462 C or 863 F

3. Venus Tilt
177.3 degrees
What does this mean? It is almost upside down.
It rotates backwards- clockwise
Does not have seasons almost no tilt.

4. Habitability Zone

5. Venus Just inside the habitability Zone. Too hot for liquid water
Liquid water acts as a buffer, High Specific heat absorbs lots of energy.
It also absorbs lots of CO2 keeping it out of the atmosphere.
Animals especially sea life takes the CO2 in the water and stores it safely away. Sea shells lime rock etc.

6. Atmospheres of the triad

7. Venus

8. Earth

9. Mars

10. What does life need?
Liquid water
Energy
Organic molecules

11. Greenhouse affect Visible light comes through easily.
Energy is absorbed and is given back off as infrared radiation
The greenhouse gases absorb the infrared waves very efficiently.
They then reradiate it in all directions sending a lot back toward the planet.
This traps the energy like a blanket.

12. Greenhouse gases CO2- Carbon Dioxide CH4- Methane H2O- Water Vapor
O3- Ozone

13. How that all works

14. Freezing point of water
Greenhouse affect is the difference in the predicted temperature and the actual temperature.
0 C, 32 F, or 273K
Earth is only slightly above the freezing point of water.
If we did not have a greenhouse affect the world would be frozen.

15. Venus Resurfacing Many craters but not as many as we would think.
No heavily cratered regions- all areas about the same crater densities.
The whole surface was renewed at about the same time.
It was resurfaced about 500million years ago by widespread volcanic activity.

16. Venus Interior