[neilep (OP)]

Dearest Sphericalologists,


How are ewe today ? I'm ok, going shopping later for some tetra-neons....what about ewe  ? any plans later ? want to meet up to discuss sheep and sheep related topics ? ( no digression here !!)



 
As a Sheepy I of course am NOT an accretion disc... I am in fact a cloud with legs ! just look up on any inclement day.....................there I am ! wave your arms when ewe do as I need the target practice !!




So, what's the oort cloud all about ? why's it so special that it has to be all cloudy and not accretiony ??


As a firm believer in empirical study, yesterday I went and visited "oorty"...we are BFFs now !!





Oorty and I becoming BFFs just yesterday as confirmed in this bona-fide non doctored 1-1 scale image


So, as ewe can see, Oorty is cloudy !!...why's that then ? why is Oorty NOT an accretion disc ?

If ewe could let me know asap please because I have a Yoga-Cise class to give (it's where ewe exercise your jaws in a meditative way by consuming copious amounts of Yogurt)...and I would like to bring this up for discussion.

So,


Why is Oorty Spherical ?

Hugs et les shmishes

mwah mwah mwah


Sheepy
ExecEWEtive Sheep In Charge Of Asking This Kweschun




Oh Oorty
Why Cloudy ?
Why Roundy ?
Ewe are so big and looking kewl
My BFF is not spherical !!

[paul cotter]

Seems nobody, me included, has any useful info. Spherical, oval, ovine?, nah, scrap that line of investigation, I need a better analogy to ram home my point.

[Petrochemicals]

I would think it is because the gravitational attraction is too weak.

[Zer0]

Bcoz Gravity is Directly proportional to Mass, & Inversely to the Square of Distance.

Prapz ewe needs to make sum new friendz in the Kuiper Belt.

ps - baa baah ewe!

[neilep (OP)]

Seems nobody, me included, has any useful info. Spherical, oval, ovine?, nah, scrap that line of investigation, I need a better analogy to ram home my point.

I appreciate ewer attention Paul. I am sheeprised myself to have this topic left BAAron !!

[Petrochemicals]

Seems nobody, me included, has any useful info. Spherical, oval, ovine?, nah, scrap that line of investigation, I need a better analogy to ram home my point.

I appreciate ewer attention Paul. I am sheeprised myself to have this topic left BAAron !!

Personally I would have thought people should have flocked to be part of the fold, I think you have been fleeced.

[paul cotter]

Or sheared.

[evan_au]

I expect it is because:
- The temperature is so low this far from the Sun, that most of the volatiles have condensed onto compact icy comets and asteroids. So there is effectively no wind resistance out there.
- The density of the icy bodies this far from the Sun is so low that they hardly ever collide with each other.
- The average size of the bodies is pretty low (eg Pluto-sized and smaller), so they don't interact strongly via gravity (we do see the occasional long-period comet)
- That means they don't exchange angular momentum, and so they stay on their original, random trajectories, forming a diffuse ball.

In contrast, the inner accretion disk (nearer the Sun) was full of hot gas, with asteroids frequently running into each other and exchanging angular momentum through collisions and (for the bigger objects) through gravitational interactions.
- As a result of gravitational interactions, many objects would have plunged into the Sun, or been thrown out of the Solar system altogether
- Eventually, after many interactions, the whole inner solar system would have settled down to the average angular momentum of the original cloud from which the inner solar system formed.
- This resulted in a planar arrangement of the planets with a common axis. This then minimised subsequent interactions, and is a fairly stable arrangement (if isolated from outside influences).

[Petrochemicals]

I would think it is because the gravitational attraction is too weak.

Although on further reflection I think this is incorrect. If the accumulated matter of the solar system including the Oooooooooooooort cloud was to clump together in the barreness of space it would signify that the gravitational attraction was indeed great enough. Why is there an asteroid belt rather than being consolidated? I think there is a reason for that but I cannot remember, something like the jupiter migration.

[evan_au]

Why is there an asteroid belt rather than being consolidated?

One suggestion I heard was that the gravitational tug of Jupiter was greater than the self-gravitation of the asteroid belt, so it prevented the asteroid belt from coalescing into a single body.
...But that was before the more recent theories about planetary orbits migrating around.