activity a (continued from previous page) 5. classify: astronomers classify the eight planets in our solar…

activity a (continued from previous page) 5. classify: astronomers classify the eight planets in our solar system into two groups: terrestrial planets and gas giants. terrestrial planets have rocky surfaces, while gas giants are composed mainly of gas. based on your data, classify each planet as a terrestrial planet or a gas giant. (hint: look at the density of each planet.) mercury: ____________ jupiter: ____________ venus: ____________ saturn: ____________ earth: ____________ uranus: ____________ mars: ____________ neptune: ____________ 6. summarize: compare the masses, radii, and densities of the terrestrial planets and the gas giants. a. what do the terrestrial planets have in common? ____________ b. what do the gas giants have in common? ____________ 7. extend your thinking: why doesnt pluto fit into either the terrestrial planet group or the gas giant group? ____________ 8. think and discuss: why do you think the inner planets are small and dense, while the outer planets are gas giants? if possible, discuss your ideas with your classmates and teacher. ____________

activity a (continued from previous page) 5. classify: astronomers classify the eight planets in our solar system into two groups: terrestrial planets and gas giants. terrestrial planets have rocky surfaces, while gas giants are composed mainly of gas. based on your data, classify each planet as a terrestrial planet or a gas giant. (hint: look at the density of each planet.) mercury: ____________ jupiter: ____________ venus: ____________ saturn: ____________ earth: ____________ uranus: ____________ mars: ____________ neptune: ____________ 6. summarize: compare the masses, radii, and densities of the terrestrial planets and the gas giants. a. what do the terrestrial planets have in common? ____________ b. what do the gas giants have in common? ____________ 7. extend your thinking: why doesnt pluto fit into either the terrestrial planet group or the gas giant group? ____________ 8. think and discuss: why do you think the inner planets are small and dense, while the outer planets are gas giants? if possible, discuss your ideas with your classmates and teacher. ____________

Answer

Answer:

Mercury: Terrestrial planet Venus: Terrestrial planet Earth: Terrestrial planet Mars: Terrestrial planet Jupiter: Gas giant Saturn: Gas giant Uranus: Gas giant Neptune: Gas giant 6. A. Terrestrial planets have rocky surfaces, relatively small masses, small radii, and high densities. B. Gas giants are mainly composed of gas, have large masses, large radii, and low densities. 7. Pluto is small in size, has a unique orbit, and its composition is different from both terrestrial planets (less - rocky) and gas giants (not mainly gas - composed). It is now classified as a dwarf planet. 8. Answers may vary. One possible explanation is that during the formation of the solar system, the inner regions were closer to the Sun where it was hotter, allowing only heavier elements to condense and form small, dense terrestrial planets. The outer regions were colder, allowing lighter gases like hydrogen and helium to accumulate and form the large gas giants.

Explanation:

Step1: Recall planet - type definitions

Terrestrial planets have rocky surfaces, gas giants are gas - dominated.

Step2: Classify planets

Based on definitions, inner planets (Mercury, Venus, Earth, Mars) are terrestrial; outer large planets (Jupiter, Saturn, Uranus, Neptune) are gas giants.

Step3: Analyze terrestrial planet commonalities

Consider their physical characteristics like surface type, mass, radius, density.

Step4: Analyze gas - giant commonalities

Consider their composition and physical characteristics.

Step5: Analyze Pluto's non - fit

Consider its size, orbit, and composition.

Step6: Hypothesize on inner and outer planet differences

Base on solar - system formation theories about temperature and element condensation.