Question

How do scientists know that the universe is expanding?

The galaxies are moving away from each other, and the temperatures are decreasing.

The galaxies are moving toward each other, and the temperatures are increasing.

The galaxies are moving toward each other, and the temperatures are decreasing.

The galaxies are moving away from each other, and the temperatures are increasing.

Answer 1

Well, which 2 options can you logically rule out right off the bat? (:

Answer 2

A and D

Answer 3

Really? Doesn't it make more sense that for somethings to be expanding, they move AWAY from each other?

Answer 4

yeah you right if the galaxies are expanding they would me increasing cause expanding means larger right

Answer 5

Yes, so options B.) and C.) are ruled out

Answer 6

yes

Answer 7

Okay, so you're left with the temperature factor to choose from. Just using your common sense, if somethings were getting pulled closer together, would the temperature between them get colder or warmer?

Answer 8

it would get warmer

Answer 9

Exactly. So if they're pulling apart their temperature would...?

Answer 10

decrease

Answer 11

so it would be A

Answer 12

thank you so much

Answer 13

You got it.

Answer 14

No problem - glad i can help