Observation by john simpson: R.Mon & NGC2261 Polarimetry

Uploaded by

john simpson

Observer

john simpson

Observed

2018 Feb 24 - 20:35

Uploaded

2018 Aug 07 - 23:16

Objects

Hubble's Variable Nebula (NGC2261)

Equipment
  • Celestron C6
  • Astrodon [J-C] V-band filter
  • WollastonPrism
  • ATIK 314L+
Exposure

60 sec.

Location

SW Scotland

Target name

R.Mon/NGC2261

Title

R.Mon & NGC2261 Polarimetry

About this image

R.Mon listed as Herbig Ae/Be star in Simbad. It’s the source of illumination/excitation of nebula NGC2611. The figure shows a composite of linear polarisation images taken at 0, 45, 90,135 deg. [20 exposures each of 60seconds]. The Wollaston prism splits the incoming beam into 2 orthogonally polarised beams from which are calculated Stokes Q & U as well as linear polarisation magnitude and angle. Considerable debate in the past about the nature and geometry of the polarised gas & dust surrounding R.Mon as a result of the large variations in measured polarisation magnitude & angle on time-scales of months/years. Typically these have ranged from 10-15% and 70-100 deg. respectively.   This target probably the limit of what I can measure. Also had some problems with tripod & tracking, hence the oval stars, but still enough data to measure the polarisation. In this instance R.Mon magnitude estimated to be 13.9% with polarisation ellipse at an angle of 65.3 deg.  Still looking at how [and if possible] to extract polarisation characteristics of  the nebula. All good fun though.

Files associated with this observation
Like this image
Copyright of all images and other observations submitted to the BAA remains with the owner of the work. Reproduction of work by third parties is expressly forbidden without the consent of the copyright holder. By submitting images to this online gallery, you grant the BAA permission to reproduce them in any of our publications.