A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Others » Astro Pictures
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Annual Hubble's Variable Nebula Comparison



 
 
Thread Tools Display Modes
  #1  
Old February 26th 17, 09:23 PM
WA0CKY WA0CKY is offline
Senior Member
 
First recorded activity by SpaceBanter: Feb 2008
Posts: 689
Default Annual Hubble's Variable Nebula Comparison

Hubble's Variable Nebula aka NGC 2261, is a highly variable nebula in Monoceros. Famous for being the first light image of the 200" Palomar Telescope in 1949 taken by Edwin Hubble himself. Movies of the nebula show it varies quite a bit over only a couple days time. Unfortunately, all my attempts to catch this have failed due to horrid weather and my failing to keep trying as my to-do list beckons strongly. So I've settled for once a year. Even then variable seeing and transparency makes for a difficult comparison. Last year I tried extra hard to get a series only days apart but the weather had other ideas. Best I could do in 2014 was two images; one my last image of 2013 and another on February 19, 2014, 51 days apart rather than a year two or three days. In all other years I only managed the one image a year.

I've included my annual (and twice annual from the winter of 2013-14) images since 2011. Color of the 2011 image is highly suspect. Exposure times vary as does my processing so these aren't usable for scientific comparison. Thanks to bad weather this year while I got 4 luminance frames frames they were through clouds that limited my ability to pull out faint details. I took my usual 2 color frames but for the clouds only one of each was usable. Being highly variable due to the clouds I had to do severe color balancing that is likely only somewhat successful but was all I had to work with. Seeing however was better than average as the star southeast of the illuminating star is easily seen but in many prior years was lost in the glare and fuzz of the illuminating star. Some of this was due to poor transparency dimming the illuminating star but mostly I think it was seeing that helped it be resolved. Being a variable star I may have caught it near its minimum as well.

Note that not only does the nebula change above the illuminating star but the faint hook shaped piece of nebulosity south of the star also has changed. Being faint some of this is likely conditions. In 2011 it was rather obvious but then it faded. Last few years the part of the hook coming back north is getting stronger but the down-stroke is virtually gone. North of the star the main changes are on the east side though the dark band crossing the lower part of the nebula that was strong a few years ago has vanished in 2015 but seemed to be returning in 2016 only to vanish this year. I expect there were lots of other changes I missed due to the very long time between images. The color in the 2011 image is somewhat suspect as my attempts at color balance were primitive back then. Likely it is redder than it would have been if processed today. I suppose I should go back and redo it.

R Mon, the variable star at its base, illuminates the nebula. It is a brand new star just exiting its birth cocoon. It is thought dust clouds from this cocoon are still orbiting the star casting various shadows on the nebula causing the variations in its details and color. In animations taken only days apart it appears illumination of the nebula flows upward from the star hitting more distant parts of the nebula over time. This gives an illusion of material moving but I am quite certain this is more like shining a flashlight beam around on a mostly stationary object. The first animation link is from a University observatory, the second is by amateur Tom Polakis in Tempe, Arizona where clear skies are much more common than here.
http://umanitoba.ca/faculties/scienc...animation.html
http://m2.i.pbase.com/o9/64/297864/1...1_200_crop.gif

Data for my January 28, 2017 image (UT)
14" LX200R @ f/10, L=4x10' RGB=1x10', STL-11000XM, Paramount ME

Rick
Attached Thumbnails
Click image for larger version

Name:	HVN17L4X10RGB1X10.JPG
Views:	433
Size:	457.8 KB
ID:	6526  Click image for larger version

Name:	HVN17L4X10RGB1X10CROP.JPG
Views:	176
Size:	171.5 KB
ID:	6527  Click image for larger version

Name:	HVN2010-2017.JPG
Views:	289
Size:	455.2 KB
ID:	6528  
  #2  
Old March 14th 17, 10:57 PM
slilge slilge is offline
Senior Member
 
First recorded activity by SpaceBanter: Aug 2008
Posts: 151
Default

Rick,

that's an impressive sequence of high resolution images. I'd really like to see a timelapse of this nebula with e.g. a one week interval. But that would need a space telescope to accomplish...

Stefan
 




Thread Tools
Display Modes

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

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Annual Gyulbudaghian's Nebula comparison image WA0CKY Astro Pictures 1 February 18th 17 01:43 PM
Annual image of Hubble's Variable Nebula WA0CKY Astro Pictures 0 September 15th 13 03:36 AM
Comparison 2 shots (2005-2011) of the Hubbles Variable Nebula: NGC 2261 Danilo Pivato Amateur Astronomy 4 March 14th 11 11:21 AM
Hubble's Variable Nebula Rick Johnson[_2_] Astro Pictures 1 January 3rd 07 11:13 PM
Hubble's Variable Nebula Bill Ferris Amateur Astronomy 0 January 18th 04 07:22 PM


All times are GMT +1. The time now is 12:12 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.