(03-29-2021, 08:37 PM)Jags Wrote: Here’s a HB question, along with others that may have insight or curiosity.  I was watching a show that said the planets orbit the sun counterclockwise.  Well, that’s when viewed  from the sun’s northern pole.  When viewed from the southern pole it will be clockwise.  So, my question is multi parts.  Which is it?  Also, is the rest of the galaxy and galaxies all on the same plane?  Doesn’t make sense to me that everything is all on the same plane.  So is it a “flat” universe?  If so, wouldn’t that make all galaxies revolve around the same central entity?  Would that entity be a small part of others all doing the same thing?   Ugh.  Can go on and on.

Depending on the point of view, the planets would orbit CW or CCW. It's just human nature to view things from what we consider overhead. If someone likes to view things from the bottom, well, there's nothing wrong with that.

There's several types of galaxies but not all rotate on a common plane. Some don't even rotate. Our galaxy, as with other barred spiral galaxies, rotates on a plane because these types of galaxies orbit around super massive black holes which provide the tremendous gravity well that provides the counter force to matter traveling in a straight line. Thus, rotation. The black hole at the center of our Milky Way galaxy is called Sagittarius A* (the asterisk is pronounced as star). The Milky Way is about 150,000 light years across and about 10,000 light years thick at the center and rotates around an object with a gravitational pull so strong that it holds all of that matter captive. 

The universe does not operate on a plane. Galaxies are spread in all directions and form groups, clusters and filaments. Filaments are the largest known structures in the universe. They consist of hundreds of thousands of galaxies (each galaxy potentially hundreds of thousands of light years across) and are mind bogglingly immense in size - hundreds of millions of light years in length. Like the Sloan Great Wall. Amazingly, these galaxies are gravity bound into these immense structures even though they are several million light years distant from each other. For instance, the Milky Way and the Andromeda galaxy, which are part of a local group of galaxies, is 2.5 million light years distant and will collide in about 5 billion years because they are gravitationally attracted and are currently closing that distance at about 68 miles per second. For reference, a light year is equal to 5.8 trillion miles. 

To truly understand the immensity of space, you have to have your mind right. I've known people who didn't want to talk about it because it upsets their comfortable world view. To grasp it realistically illustrates just how delicately tentative life and our world actually are.

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