While the human body remains a mystery even to scientists who study it their entire lives, it is not the only far frontier. Astrophysicists find outer space equally difficult to explore and explain, and they too have considered practical and technical uses for origami. A team at San Bernardino Valley College in Southern California created Starshade, a large structure that looks like a sunflower and acts like a pair of sunglasses: By blocking out a star's overpowering rays of light, the device helps a telescope produce a clearer image of the planets that orbit the star. What analogy is used in this paragraph?

1. seamount a raised footwall block between normal fault creates this 2. syncline break between rocks where a hanging wall rises relative to a footwall 3. hot spring on rolling hills, this a dip between hills 4. volcanic neck created when a block with hanging walls slips down between normal faults 5. caldera underwater volcano that never reaches above sea level 6. horst natural hot water on earth's surface containing many minerals 7. graben underwater volcano whose top is eroded flat by waves 8. crater less than a mile in diameter; looks like a bowl at the top of a volcano 9. guyot magma that filled the central vent that remains after the volcano has eroded 10. reverse fault over 1 mile in diameter; looks like a bowl over a volcano