Download Ch. 25.3 The Inner Solar System (pages 803 – 809)

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Ch. 25.3 The Inner Solar System (pages 803 – 809)
Inner “Terrestrial” Planets: Mercury, Venus, Earth, & Mars
Directions: Use your notes, book, and the figures provided to answer the following questions.
Figure 1: Inner planets & Pluto
Figure 2: Inner vs. Outer Planets
Figure 3: Planets vs. the Sun
Figure 12, page 804
1.
Which two inner planets are the closest in size? Venus & Earth
2.
Which inner planet has the shortest revolution period? How long is it? Mercury; 88 days
3. Which inner planet has the longest revolution period? How long is it? Mars; 1.8 years
4. Which inner planet has days that are a close match to our Earth days? Mars
Mercury
5. What are surface temperatures like on Mercury? Why is that? Extremely hot or extremely
cold; It has no atmosphere to block solar radiation. The side facing the sun is hot. It has no
atmosphere to trap outgoing heat. The side facing away from the sun is cold.
6. Is Mercury geologically dead? Support your answer. Yes. It has no active volcanoes (smaller
core, cooled down)
Venus
7.
What is unusual about Venus’s rotation and revolution? It rotates backwards (spins in the
opposite direction compared to other planets) and it rotates so slowly that a day is longer than a
year (revolution)
8. What is the atmosphere like on Venus? Be specific. Thick CO2
9. What are temperatures like on Venus? HOT!!!!
10. What produced the atmosphere on Venus? Volcanoes
11. Can there be liquid water on Venus? Why or why not? No it is too hot. All water is steam or
water vapor (clouds)
12. What happened to the Soviet spacecraft that visited Venus? It was destroyed by high
temperatures, pressures, winds, and acidic conditions.
Earth
13. What conditions make Earth unique in our solar system (What do we have that other planets
don’t)? The right temperatures and pressures for liquid water (and life).
14. Describe Earth’s atmosphere (Gases and %s)? Nitrogen (78%) and oxygen (21%); 1% other
gases (carbon dioxide etc.)
15. What happens on Earth to remove some carbon dioxide, so that it does not accumulate (like
Venus)? Photosynthesis by plants.
16. Is Earth geologically dead or active? Support your answer. Active. Earth has active volcanoes
and plate tectonics.
Mars
17. Why is it called the “Red Planet”? Red-orange soil & rocks (iron in rocks)
18. Is Mars volcanically active today? NO
19. Describe the Martian atmosphere. Thin CO2
20. Describe temperatures on Mars. Very cold, frozen
21. What features lead scientists to believe that Mars once had liquid water on the surface?
Dry river beds or channels
22. Where is the water on Mars today? (2 sources/locations)
Frozen in an ice cap or frozen in the ground (under the surface)
Asteroids
23. What are asteroids? Space rocks with ice and metal
24. Where are they found? Between Mars and Jupiter
25. How did asteroids form? Remnants of pieces that did not form planets.