Celestial hemisphere:  Northern  ·  Constellation: Cassiopeia (Cas)
Getting plate-solving status, please wait...
SH2-170 The Little Rosette, niteman1946
SH2-170 The Little Rosette
Powered byPixInsight

SH2-170 The Little Rosette

Getting plate-solving status, please wait...
SH2-170 The Little Rosette, niteman1946
SH2-170 The Little Rosette
Powered byPixInsight

SH2-170 The Little Rosette

Equipment

Loading...

Acquisition details

Loading...

Description

Sh2-170 the “Little Rosette” is a emission nebula visible in the Cassiopeia constellation. 

It is located in the northwestern part of the constellation, about 5 ° north of the star Caph.  The most suitable period for its observation in the evening sky falls between the months of August and January and is considerably facilitated for observers located in the regions of the terrestrial northern hemisphere, where it is circumpolar up to the warm temperate regions. 
Sh2-170 is a H II region located on the Arm of Perseus about 2300 parsecs (about 7500 light years) away, near the edge of a large super bubble originating from the combined action of the stellar wind of the Cassiopeia stellar association OB5.  Responsible for the ionization of its gases is the star known by the initials BD + 63 2093; it is a main sequence star with spectral class O9V, part of the small and young open cluster Stock 18.
The edges of the ionized region are mostly blurred, indicating a lower density at the periphery, except for the south-eastern side.  The ionizing star is located near the center, on the leading edge of a small isolated molecular cloud. It is believed that 40% of the mass of the complex consists of mono atomic neutral hydrogen (HI), located beyond the ionization front.  
The infrared radiation source IRAS 00001 + 6417, observable in the direction of the nebula, corresponds to a molecular cloud with CO emissions probably located at a greater distance, around 4600 parsecs.  Although the Avedisova Catalog indicates the source as being linked to Sh2-170.  [Ref:  Wikipedia It]

CAPTURE Information: 
The image was captured with the iOptron CEM120 mount , the venerable Meade 12"LX200 SCT OTA, and my QHY295m Pro mono cmos camera at F7.16 (2182mm FL).  Image subs were taken through Astronomik's narrowband filters of Ha, OIII and SII. 

IMAGE information -- 2022
Ha (300s): 70 subs (5.83 hrs.) on Oct 18th, 20th and 26th, 2022.
OIII (300s): 70 subs (5.83 hrs.) on Oct 18th, 20th and 26th, 2022.
SII  (300s): 68 subs (5.67 hrs.) on Oct 18th, 20th, 21st and 26th, 2022.

All subs  were shot at 300s and -10C.  All exposures were done at 1x1 bin, Gain 1600 and Offset 56.  Lights, Darks, Flats and Flat Darks were used for processing. 

Processing was done in PixInsight following, for the most part, kayronjm's tutorial of Feb. 24th from several years back. 
Credit also goes to Rick Stevenson’s Color Mask Script and Christopher Gomez’s tutorial.
This is a slight  crop owing to little movement between subs.

COMMENTS:
It appears that this is the second time I’ve imaged this target. The first was in 2020 using my departed Atik 383L+mono CCD.  I believe at that time there wasn't much to look at.

ONE LAST THING:
My CEM120 iOptron mount has been back to the Massachusetts service center twice to correct for problematic tracking.  And I had commented previously that I was having to trash out about 20% of the subs.  Since then, with guidance from iOptron, I loosened the RA drive belt and the results have been positive while still mixed.  While I'm loosing much fewer subs, there is still a problem where the excursions in RA are so great that the guide star gets lost.  This has been reported to iOptron and they have yet to respond.

Comments

Sky plot

Sky plot

Histogram

SH2-170 The Little Rosette, niteman1946