The rotation period of the Milky Way is 225 million years.

Look at the temperature line on the graph below and see if you think there is a relationship. What was the temperature 225M years ago> 450M years ago?

This is the effect that gravity has on Global Temperature.

Sometimes we are experiencing Universe PLUS the 2/3 Milky Way, Sometimes Universe MINUS 2/3 Milky way. (Remembering we are not right at the edge of the Milky Way.)

In the next images, see the location and path the Sun takes through the Milky Way, and what the movement is of significant objects around us.