We receive today the light from a distant galaxy and from its spectrum we conclude that it took 400 Myr for the photons to reach us. Which one of the following statements is correct? O The Universe is accelerating, so that galaxy is moving toward us at higher speed and it will take less than 400 Myr for future photons from that galaxy to reach us. O That galaxy is 400 million light years away from us today. O That galaxy is moving away from us, so today it is more distant from us than 400 million light years. O We are observing that galaxy as it was in the past, and today it is accelerating toward us.

We receive today the light from a distant galaxy and from its spectrum we conclude that it took 400 Myr for the photons to reach us. Which one of the following statements is correct? O The Universe is accelerating, so that galaxy is moving toward us at higher speed and it will take less than 400 Myr for future photons from that galaxy to reach us. O That galaxy is 400 million light years away from us today. O That galaxy is moving away from us, so today it is more distant from us than 400 million light years. O We are observing that galaxy as it was in the past, and today it is accelerating toward us.

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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