<p>When an embedded cluster forms and later blows away gas to become a young open cluster the stars inside interact gravitationally. They have essentially random velocities relative to each other, performing a chaotic dance. This typically makes the heavier (and hence brighter) stars end up near the core with low velocities and the lighter stars get into higher orbits. The phenomenon is called <a href="https://en.wikipedia.org/wiki/Mass_segregation_(astronomy)" rel="nofollow noreferrer">mass segregation</a> and happens because all stars end up with roughly similar kinetic energy. </p>

<p><a href="https://arxiv.org/abs/astro-ph/0003390" rel="nofollow noreferrer">The effect is more extreme in globular clusters</a> since they can persist for a long time, while open clusters tend to dissolve by interacting with the rest of the galaxy. In a way, as the cluster dissolves the lighter stars will be moving away ("radiating") from the core, although at this stage they are all mostly doing the kinetic energy exchange dance. </p>

CC BY-SA 4.0
2020-12-22T19:03:14.613Z
If an ejection trajectory qualifies for “higher orbits”, then the description is accurate.
Incnis Mrsi
CC BY-SA 4.0
2020-05-24T23:13:56.123Z
2020-05-24T23:13:56.123Z
Anders Sandberg
<p><a href="https://www.nasa.gov/multimedia/imagegallery/image_feature_476.html" rel="nofollow noreferrer">https://www.nasa.gov/multimedia/imagegallery/image_feature_476.html</a>
<br>Please notice especially the bright star at the center of the image, and how the most massive stars have etched out a cavity in the HI and molecular cloud. It is noticeable that the star near the center that has a number of stars seemingly radiating from it.</p>

<p>What kind of process could create such stellar radiating structures, if real?<br> 
<br>Is the spacing related to the Jeans radius? <br> <br>Thank you.</p>

<p><a href="https://i.sstatic.net/XTaVd.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/XTaVd.jpg" alt="enter image description here"></a></p>

CC BY-SA 4.0
2020-05-24T12:40:51.917Z
This is https://en.wikipedia.org/wiki/NGC_2264 but that article doesn't say anything about the formation.
PM 2Ring
<astrophysics>
What kind of process could create such stellar radiating structures, if real?
Boris
# What kind of process could create such stellar radiating structures, if real?

(Asked by: username_0 on 2020-05-24)

<https://www.nasa.gov/multimedia/imagegallery/image_feature_476.html>
  
Please notice especially the bright star at the center of the image, and how the most massive stars have etched out a cavity in the HI and molecular cloud. It is noticeable that the star near the center that has a number of stars seemingly radiating from it.

What kind of process could create such stellar radiating structures, if real?  
  
Is the spacing related to the Jeans radius?   
   
Thank you.

[![enter image description here](https://i.sstatic.net/XTaVd.jpg)](https://i.sstatic.net/XTaVd.jpg)

**Tags:** astrophysics

> **Comments:**
> **username_1**: This is https://en.wikipedia.org/wiki/NGC_2264 but that article doesn't say anything about the formation.  

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## 1 answers

### Answer by username_2 on 2020-05-24. Score: 2 | Accepted answer

When an embedded cluster forms and later blows away gas to become a young open cluster the stars inside interact gravitationally. They have essentially random velocities relative to each other, performing a chaotic dance. This typically makes the heavier (and hence brighter) stars end up near the core with low velocities and the lighter stars get into higher orbits. The phenomenon is called [mass segregation](https://en.wikipedia.org/wiki/Mass_segregation_(astronomy)) and happens because all stars end up with roughly similar kinetic energy.

[The effect is more extreme in globular clusters](https://arxiv.org/abs/astro-ph/0003390) since they can persist for a long time, while open clusters tend to dissolve by interacting with the rest of the galaxy. In a way, as the cluster dissolves the lighter stars will be moving away ("radiating") from the core, although at this stage they are all mostly doing the kinetic energy exchange dance.

> **Comments:**
> **username_3**: If an ejection trajectory qualifies for “higher orbits”, then the description is accurate.  

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