Go Back   IceInSpace > General Astronomy > Astronomy and Amateur Science

Reply
 
Thread Tools Rate Thread
  #1  
Old 26-07-2020, 10:32 PM
Stonius's Avatar
Stonius (Markus)
Registered User

Stonius is offline
 
Join Date: Mar 2015
Location: Melbourne
Posts: 1,081
Does anyone know the cause of this periodic anomaly near the Keyhole Neb?

I've noticed this structure that repeats fairly regularly just below the keyhole nebula. Below is a crop of my photo, but it's not an artifact, as you'll see the same structures in other images posted on the web depending on how they've processed them.

It consists of 4 dark bars (and as many as 6, though the other two are not as clearly defined and therefore a bit 'iffy')

Given the Keyhole structure is about 7LY across (and assuming the structures are contiguous with the greater nebula) I'd make the bars as being about 3LY long, spaced about 3LY apart.

If you look just to the north at Hubble's view of the Mystic Mountain region, you can again see a periodicity in the jets of young stars. Of course, now I'm starting to look for it, I'm seeing periodic features everywhere -in other nebulae too, like in the below Hubble shot of the Lagoon Nebula.

We know that the solar wind from newly formed stars creates these bubble-like voids in the surrounding gas and dust. Perhaps this would suggest a cyclical phase in early star formation?

I'm speculating here, but perhaps some stars don't just switch on and 'start shining', but instead waver across the threshold of viability several times before they reach a stable state. A possible mechanism would be if the energy from fusion creates expansion that, together with the loss of density would serve to put the brakes on the fusion reaction temporarily until the star had cooled, become more dense and more matter had collected to kick start the process again. Perhaps this happens a few times until it can sustain the reaction?

Alternatively I guess the same thing could be caused by a polar jet from a rotating object, I suppose?

It's an interesting feature, I suppose, and not one I have noticed before, even though I've looked at that image a hundred times or more!


Cheers


Markus
Attached Thumbnails
Click for full-size image (Carinae Bars.jpg)
192.3 KB51 views
Click for full-size image (Mystic Mountains.jpg)
136.8 KB49 views
Click for full-size image (Lagoon.jpg)
75.9 KB46 views

Last edited by Stonius; 27-07-2020 at 12:55 AM.
Reply With Quote
  #2  
Old 27-07-2020, 07:46 AM
xelasnave's Avatar
xelasnave
Gravity does not Suck

xelasnave is offline
 
Join Date: Mar 2005
Location: Tabulam
Posts: 13,805
Great images for a start...probably some dates would help..and have you looked at other images? My guess is it may be seeing .. however it would be wonderful if you are onto something.
Alex
Reply With Quote
  #3  
Old 27-07-2020, 08:05 AM
xelasnave's Avatar
xelasnave
Gravity does not Suck

xelasnave is offline
 
Join Date: Mar 2005
Location: Tabulam
Posts: 13,805
Maybe ...https://youtu.be/lh0skjMpJHo ..not sure if particularly relevant but interesting things about variations.
Alex
Reply With Quote
  #4  
Old 27-07-2020, 08:15 AM
Stonius's Avatar
Stonius (Markus)
Registered User

Stonius is offline
 
Join Date: Mar 2015
Location: Melbourne
Posts: 1,081
Quote:
Originally Posted by xelasnave View Post
Great images for a start...probably some dates would help..and have you looked at other images? My guess is it may be seeing .. however it would be wonderful if you are onto something.
Alex

Thanks, but the other two images were Hubble's, not mine - sorry I should have been more explicit.


The data for the Keyhole image was aquired Feb 2019.
Reply With Quote
  #5  
Old 27-07-2020, 08:23 AM
Stonius's Avatar
Stonius (Markus)
Registered User

Stonius is offline
 
Join Date: Mar 2015
Location: Melbourne
Posts: 1,081
And again in M42


Original Photo from exaxe
https://www.cloudynights.com/topic/6...ort-exposures/
Attached Thumbnails
Click for full-size image (M42 Periodicity.jpg)
55.9 KB41 views
Reply With Quote
  #6  
Old 27-07-2020, 02:42 PM
Stonius's Avatar
Stonius (Markus)
Registered User

Stonius is offline
 
Join Date: Mar 2015
Location: Melbourne
Posts: 1,081
And again in the tarantula
Attached Thumbnails
Click for full-size image (Tarantula.jpg)
79.2 KB26 views
Click for full-size image (Tarantula2.jpg)
115.0 KB20 views
Reply With Quote
  #7  
Old 27-07-2020, 11:10 PM
Stonius's Avatar
Stonius (Markus)
Registered User

Stonius is offline
 
Join Date: Mar 2015
Location: Melbourne
Posts: 1,081
Quote:
Originally Posted by Stonius View Post
I'm speculating here, but perhaps some stars don't just switch on and 'start shining', but instead waver across the threshold of viability several times before they reach a stable state. A possible mechanism would be if the energy from fusion creates expansion that, together with the loss of density would serve to put the brakes on the fusion reaction temporarily until the star had cooled, become more dense and more matter had collected to kick start the process again. Perhaps this happens a few times until it can sustain the reaction?

Duh! Guess I just surmised the existence of the Kappa opacity mechanism that drives Cepheid Variables. Only 57 years after John Cox discovered it.


Still, it would be goo to know if a similar mechanism is causing these structures.


Markus
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 03:48 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Testar
Advertisement
NexDome Observatories
Advertisement
Limpet Controller
Advertisement
Astronomy and Electronics Centre
Advertisement