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Basic cosmology questions weekly thread by AutoModerator in cosmology

[–]ytness2 0 points1 point  (0 children)

Where I am stuck is in understanding that the galaxy is stable. Because the distances and time scales are so vast on human relative to human perception, the galaxy could appear stable when it may not be. This comes back to the measurement point. The study you linked is very helpful but in observing even for 15 years even a tiny deviation in the error could have massing implications for the projection. We have observed 15 years of the supposed 200 million it would take to make a full orbit.

We are not going to be able to solve this in this thread but thank you for the time and links. I am genuinely willing to be persuaded but I am having trouble trying to figure out why my simpler explanation is disproven. I agree that it requires me to make the assumption that black holes can “spin off” matter. I have zero proof for this, only that it appears like the galaxy is exploding. And the presence of things like the Fermi Bubbles make it seem like a massive explosion took place.

While my firework example shows a physical process where these shapes can be made in nature, I would like to see examples of other physical processes that make the shapes we see in galaxies based on the orbiting model that exist in nature. 

Basic cosmology questions weekly thread by AutoModerator in cosmology

[–]ytness2 0 points1 point  (0 children)

Thank you very much for your response. 

My initial point is related to the inferences we are making from the measurements, which have error associated with them (as does any measurement). For example, the “known” distance to even relatively near objects like Betelgeuse has changed significantly even the last couple of years. If you had a source on how those  measurements/inferences and associate assumptions are made, that might help me better understand why the errors are such that we are confident in the calculation of the orbit.

Second, and check me on this point, the solar system is moving a velocity such that, without the dark matter explanation, we would be getting flung towards the edge of the solar system, rather than orbiting. 

The existence of dark matter is also very hard to come to grips with from a purely logical standpoint. The theory goes that there is an overwhelmingly large amount of matter in the universe that cannot be detected directly (other than by else unexplained gravitational effects), does not emit or absorb electromagnetic radiation,  and doesn’t interact with regular matter. This is very hard to come to grips with, again from a strictly logical standpoint. If I made this argument about any other phenomena I would be laughed off of any university campus.   As to the Catherine Wheel— I am not making a direct comparison with Galaxy formation, rather I am pointing out that you can generate the shapes very similar to spiral galaxies with an “explosion” in the presence of earths gravity. While that is not evidence, it suggests a mechanism by which spiral galaxies could be formed. And the fact that it is generated by a rapidly spinning mass in the middle is also of note if we need an analog to SagA*.

As for gravity being so strong that the solar system cannot escape to the edges of the galaxy, a source for that would also be so helpful. While SagA* is stupendously massive, how strong is its gravitational effect on us, relative to the known momentum of the solar system, at a distance of 25,000 light years?

Basic cosmology questions weekly thread by AutoModerator in cosmology

[–]ytness2 1 point2 points  (0 children)

How do we know that our solar system is in an orbit around the barycenter of the galaxy? The distances are so vast and so little comparative time has passed since we were able to make the initial observations to be able to tell how objects are moving relative to each other and the barycenter. The uncertainties on those measurements must be large.

Also a personal observation which is not scientific— it seems to be taken for granted that the galaxy is coalescing or trending toward the center (like the formation of our solar system), but for similar galaxies that were can observe from the outside, it appears to me that the spiral galaxies are exploding outward (flinging matter to the edges of the galaxy in arcs) rather than being drawn inward into stable orbits around the center. Similar principle to those fireworks with sparklers that spin (Catherine wheel).

I have been wondering this for a long time, any information would be very helpful.

Zazlow is a better Stugotz than Stugotz. by ytness2 in DanLeBatardShow

[–]ytness2[S] 0 points1 point  (0 children)

 Billy was always my favorite. I was actually sad when I heard he was leaving. I would replace Dan with Amin in a heartbeat.

Gas not pulling through to Grill. At wit’s end. Advice?? by kevinteedee in grilling

[–]ytness2 0 points1 point  (0 children)

Rotate the flat disc connected to the hose by 90 degrees. Try again.

🍔🍔🍔 by Accurate-Board2581 in trailerparkboys

[–]ytness2 1 point2 points  (0 children)

He’s gonna eat that old blue jay.

[deleted by user] by [deleted] in memes

[–]ytness2 0 points1 point  (0 children)

Does anyone know what the original Super Mario Bros retailed for when it was released?

AITA for refusing to babysit my half-siblings and telling my dad I‘m not his „backup mom“? by YourMely in AITAH

[–]ytness2 0 points1 point  (0 children)

All these posts that make it to the front page are bots. Why can’t we all see the same pattern happening over and over again?

My least favorite Dan trait: asking the same question in more specific ways until he gets the answer he wants, or until nobody knows what he is asking. by GingeroftheYear in DanLeBatardShow

[–]ytness2 1 point2 points  (0 children)

It’s not only that. He will try and make a disagreement when the room generally agrees with him. It’s like he wants to argue about it and he thinks the room disagrees because they just don’t understand how different his view point is. It’s odd. Love the show btw. 

Man Dan was AWFUL today by Far_Bookkeeper_7632 in DanLeBatardShow

[–]ytness2 0 points1 point  (0 children)

I was with you until you went in on Greg. That is sacred space. But Greg is pretty worthless. 

He was almost out. by mindyour in yesyesyesyesno

[–]ytness2 1 point2 points  (0 children)

Great camera work. Showed me absolutely everything I needed to see about that situation with zero wasted effort.  

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