More on replicating shapes in space.

[ollypenrice]

I remain intrigued by the number of deep sky objects which have replicas of themselves nearby. Check out the Witch Head nebula in this sensational Orion constellation image. It has a very obvious twin. 

https://www.astrobin.com/yjd5ep/?q=orion constellation samyang 135

Olly

[ollypenrice]

Here's another one. Two 'holes' with fingers of gas ad dust emerging from them. C'mon, these things are real!

Olly

[wimvb]

Interesting. Now, of course, we need an explanation for this. Rippling waves come to mind. But then we need forces (winds) that create these waves. My guess is that features such as these are created by the stellar winds pushing matter before them. The matter itself can sometimes be ejected by stars. For example planetary nebulae that have shell like structures. Over time, such shells expand and become less pronounced. The original form, having the same origin, is still visible, although washed out and less regular.

Add to this the fact that the human mind is wired to see and seek out patterns, in order to make sense of all the visual stimuli from our surroundings.

[gorann]

Maybe this pair also qualifies as an example here:

https://www.astrobin.com/giffb5/C/

[gorann]

or why not the frog-babies:

[saac]

I think they arise because the masses of gas and dust are subject to the same physics dynamics. Differences will arise because of non uniformity of the distribution of matter within the gas clouds and the external forces driving them (radiation pressure, gravity ). However, over a large scale the overall behaviour and hence pattern of the gas clouds will share similarities.  For example, take a look at a spiral arm galaxy, you will see similarity in each spiral arm. 

Jim 

[leibek]

replicas ..........what replicas ......................??.. the universe is not fractel.

[iantaylor2uk]

10 minutes ago, leibek said:

replicas ..........what replicas ......................??.. the universe is not fractel.

The geometry of space time at the smallest length scales is not known. If space time is emergent, as is thought to be the case, and is generated by simple rules, it could well be fractal.

[ollypenrice]

12 hours ago, leibek said:

replicas ..........what replicas ......................??.. the universe is not fractel.

Shapes can resemble each other without being fractal.

 

On 06/11/2022 at 10:21, gorann said:

Maybe this pair also qualifies as an example here:

https://www.astrobin.com/giffb5/C/

Certainly a candidate.

I think that, as Jim says, the local physical forces (and particle abundances)  will be comparable.

Olly