HW2

According to the modern astronomical knowledge, what is the current age of the Universe? 1) 13.6 thousand years 2) 13.6 million years 3) 13.6 billion years 4) 20 billion years

13.6 billion years

Which of the following choices correctly lists our "cosmic address" from smallest to largest? 1) Earth, solar system, Local Group, Milky Way Galaxy, Local Supercluster, universe. 2) Earth, solar system, Local Group, Local Supercluster, Milky Way Galaxy, universe; 3) Earth, Local Group, solar system, Milky Way Galaxy, Local Supercluster, universe. 4) Earth, solar system, Milky Way Galaxy, Local Group, Local Supercluster, universe; 5) Earth, Milky Way Galaxy, solar system, Local Group, Local Supercluster, universe

4

What do we mean when we say that the universe is expanding? 1) The statement is not meant to be literal; rather, it means that our knowledge of the universe is growing. 2) Individual galaxies are gradually growing in size. 3) Average distances are increasing between clusters of galaxies. 4) Average distances are increasing between star systems within galaxies. 5) Everything in the universe is gradually growing in size.

Average distances are increasing between clusters of galaxies.

Could we see a galaxy that is 18 billion light-years away? 1) Yes, if we had a big enough telescope. 2) No, because it would be beyond the bounds of our observable universe. 3) No, because a galaxy could not possibly be that far away. 4) Yes, such a galaxy should be visible to the naked eye. 5) This is foil Four, and it is currently set to "false."

No, because it would be beyond the bounds of our observable universe.

Suppose we look at a photograph of many galaxies. Assuming that all galaxies formed at about the same time, which galaxy in the picture is the youngest? 1) the one that appears smallest in size 2) the one that is closest to us 3) the one that is reddest in color 4) the one that is farthest away 5) the one that is bluest in color

The one that is farthest away

Earth is made mostly of metals and rocks. Where did these materials come from? 1) They were made by our Sun. 2) They were produced in the Big Bang. 3) They were made by nuclear fission of uranium and other radioactive materials. 4) They were produced by nuclear fusion in stars. 5) They were created by chemical reactions in space between stars.

They were produced by nuclear fusion in stars.