Joshua 10:12-13
On the day the LORD gave the Amorites over to Israel, Joshua said to the LORD in the presence of Israel: "O sun, stand still over Gibeon, O moon, over the Valley of Aijalon."
So the sun stood still, and the moon stopped, till the nation avenged itself on its enemies, as it is written in the Book of Jashar. The sun stopped in the middle of the sky and delayed going down about a full day.
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So -- what happened to all the other 100 billion stars in our galaxy (with proper motions independent of ours) -- not to mention all the other galaxies in His created universe?
It's God's universe. He -- and only He -- can change the "rules or laws" by which it operates. (When He does so, we call it a "miracle"...)
HE changed mankind's temporal reference frame for a day.
He once did the same for me for about a picosecond of His time. Seemed like hours for me and changed my entire life's direction. In fact, that is why I'm a physical chemist. (Long, true story...)
BTW, did Joshua and/or Jashar even know what a "galaxy" was? If so, how many could he/they see? Also -- did mankind's language even have a word for "galaxy"?