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Put these objects in the correct order, from nearest to farthest from Earth: - page 46 / 59

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Suppose that, at this very moment, students are studying astronomy on planets in Andromeda. Could they know that we exist here on Earth?

Yes, because we can see stars in Andromeda, so they can see us in the Milky Way.

No, the light from the solar system has not yet reached Andromeda.

No, the light from the solar system that has reached Andromeda came from a time before the Earth had formed.

No, radio signals from terrestrial civilizations have not yet reached Andromeda.

Yes, in principle. With sufficiently powerful telescopes, they should be able to see man-made features such as the Great Wall of China on the surface of the Earth.

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