Question

Which of the following statements best describes what astronomers mean when they say that the universe is expanding? A) The average distance between stars in the Milky Way Galaxy is increasing with time. B) The observable universe is growing larger in radius at a rate of one light-year per year. C) The universe itself is not growing, but our knowledge of the universe is increasing with time. D) All objects in the universe, including Earth and everything on it, are gradually growing in size. E) The average distance between galaxies is increasing with time.

Answer 1

Answer. When scientists talk about the expanding universe, they mean that it has been growing ever since its beginning with the Big Bang. The galaxies outside of our own are moving away from us, and the ones that are farthest away are moving the fastest.