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Assignment 5:
1. Mercury
2. There is no oxygen and no water on Mars. The atmosphere is also too thin to keep out harmful UV rays.
3. Venus has almost the same mass and size as the earth.
4. Venus (sulphuric acid)
5. The orbit of Mars is much closer to the Sun than Neptune’s.
6. The Moon.
7. There is iron in the ground that gives it the red colour.
8. Sufficient oxygen and water; climate is suitable for vegetation, atmosphere correct depth and density.
9. If emergency signals are sent they reach the earth only two hours later. Sometimes the reception is very bad.
Total: 10
Assignment 6:
Assignment 7:
1. Venus and the Moon.
2. 150 million km. This is the distance that the Earth is from the Sun and where we currently survive.
3. Mercury.
4. Venus and Mars lie on either side of the Earth, not too near or too far from the Sun.
5. Yes. The nearer the planet to the Sun, the higher the average speed.
6. Possible as a result of the gravity and energy of the Sun.
Four minutes.24 x 60 minutes = 1440 minutes (it takes the earth 24 hours to rotate on its own axis)1400 minutes divided by 360 degrees = 4 minutes.
Assignment 8.1:
Questions
1. Photographs show that there are dry river beds on Mars. All the water has frozen and is collected at the poles. We surmise that there were large seas and rivers. This water is now underground.
2. The average temperature is possibly higher.
3. Mars is further from the Sun and thus receives less energy from the Sun. Although the Sun is a huge source of energy it will one day shrink and weaken.
4. One would breathe with difficulty and take shallow breathes. One would die quickly as there is too much carbon dioxide in the air.
Assignment 8.2:
Questions
1. -60 degrees
2. Day 1 18:20
Day 2 10:45
3. Day 1 14:30
- 15 degrees
4. from 06:00
5. When there is a dust storm it absorbs heat from the Sun which causes the temperature to rise. There is also carbon dioxide in the Martian atmosphere and this can also raise the temperature.
This is the closet planet to the sun. Mercury has many craters on its surface caused by asteroids which have collided with the planet. Mercury has no atmosphere or any moons. The temperature at the equator is approximately 400 degrees Celsius and at the poles it is –150 degrees Celsius.
Venus has an atmosphere of carbon dioxide that is much thicker than the earth’s atmosphere. The surface is hidden beneath thick clouds of sulphuric acid. Temperatures at the surface reach approximately 480 degrees Celsius. Venus is about the same size as the earth and has about the same mass.
As far as we know the earth is the only place in the universe where life occurs. Temperatures on the surface vary between 60 degrees and –90 degrees Celsius. Approximately two thirds of the surface is covered by liquid water.
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