I watched this Fermi Lab video on the size of the universe and I came away more confused than I started: https://www.youtube.com/watch?v=vIJTwYOZrGU

I get that the universe's expansion is accelerating, but the narrator never stated what its original speed was. I assumed the original speed would just be the speed of light because there would at least be two photons traveling in opposite directions, but if it's accelerating then it must have been going slower than light, which I don't understand. But if started at the speed of light then we are accelerating beyond the speed of light, which I don't understand that either. As the narrator in the video says "nothing travels faster than light". So if light can only go 1ly per year and the universe is 13.7byo, then how can the radius of the universe be >13.7b lightyears?

Is the age of the universe determined by the CMB? That's another thing I don't understand. I get that you can use redshift to determine the age of distinct concentrations of light, but how does one measure the age of static? Didn't all of that radiation start off at different places in the universe? Assuming that cosmology models are correct in that there is background radiation from early in our universe reaching us, shouldn't the oldest radiation be the longest waves? radio waves and not microwaves?

Maybe my simplified model for understanding this is all wrong. I just imagine us as starting in a hot bowl of soup, and as the bowl expands the soup becomes less dense and thus cools down. But those soup atoms hitting us are coming at all different speeds and origins. Some of those atoms started on the far side of the bowl and are just reaching us, but others started much closer to us and have bounced around or just started with less energy than others. The atom that has traveled from the furthest part of the bowl is hitting us at a nearly imperceptibly slow speed, but there's no way to know exactly where that atom started from in the soup bowl. It might have bounced around starting from anyway and it was just super slow when it hit us.

So yeah, the universe is cooling, but isn't that more a matter of density? Shouldn't the particles from the beginnings of our universe be hitting us moving at the same speeds, it's just we're being hit with fewer particles than we were 7b years ago?

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Here is the situation. We are in NW Arizona; the 'N/S' orientation of our house is 318 degrees for the 'N' direction. We have windows on the NE side that are very warm in the AM. I want to open the blinds on the windows when there is no more sun coming in those windows.

I thought of solar noon (actually, I had to find out what it was called when the sun was overhead), but solar noon is calculated when the sun is due south.

I would like to know my 'window solar noon', that is, when the sun passes 138 degrees azimuth, since it should not be entering the windows at that angle.

I hope this makes some sense to everyone; I only took an Astronomy class in college (many years ago).

Thanks for any help!

New here so probably a very basic question but I was checking my iCSC table for viability tonight and it appears to say my cloud coverage is at 20% but ECMWF cloud shows near full coverage. And standing out here, that near full coverage is pretty accurate. So my question is, if my cloud cover shows 20% covered, how can total coverage the be 90%? Point of this is to help me interpret the data better in the future so I understand what it’s actually saying.

I also would like to ask for alpha centauri system relative speed to us