Based on comparison with the Moon, it can be calculated that Andromeda would have to have a diameter of 35,000 km if it were at the same distance from us as the Moon. But it turns out that the distance from Earth to the Andromeda galaxy has been measured to be 6 × 1013 times farther than to the Moon. That's 60 trillion times farther. What is the true diameter of Andromeda, based on these numbers?

Based on comparison with the Moon, it can be calculated that Andromeda would have to have a diameter of 35,000 km if it were at the same distance from us as the Moon. But it turns out that the distance from Earth to the Andromeda galaxy has been measured to be 6 × 1013 times farther than to the Moon. That's 60 trillion times farther. What is the true diameter of Andromeda, based on these numbers?

The Solar System

9th Edition

ISBN:9781305804562

Author:Seeds

Publisher:Seeds

Chapter13: Venus And Mars

Section: Chapter Questions

Problem 1DQ

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