The Heart and Soul Nebulae
Located near the constellation Cassiopeia in the Perseus arm of the Milky Way lies a pair of well known nebulae, birthing stars and wonders. The well-named Heart Nebula (Sh2-190, IC 1805) and the less well-named Soul Nebula (Sh2-199, IC 1848) lie approximately 7,500 and 6,500 light years away respectively. Both are made up primarily of hydrogen gas and this condensing gas is the birth process of stars. Near the center of the Heart Nebula is an open star cluster of such newly formed stars known as Melotte 15. These stars have taken up much of the hydrogen and other gases from the nebula center and these young and bright stars light up the surrounding hydrogen gas, causing it to emit light in the red visible colors. Also of note in this image is the “fish head nebula” near the bottom of the heart, catalogued as IC 1795.
This image captures a relatively huge portion of sky and covers an area more than 600 light years across. Click here to see a fully annotated version of this image.
I find that the Soul Nebula, although a poetic match for its bigger neighbor, is poorly named. It may be difficult to see in my rendition, but in images with more defining details, I think this one should have been named the “chubby baby nebulae.”
Collecting the data
October was another cloudy one around the new-moon period. Luckily we had what looked to be a great night on the new moon. As usual, the forecast let us down a bit. Due to issues Miguel had in one of his previous outings with a Conservation Agent at Whetstone C.A., we decided to go back to our spot at Danville C.A.
Conditions
For a November outing the temperatures could have been much worse. We bottomed out at 42° F and winds never rose more than 5 mph. The forecasting apps all suggested a mostly clear night. Unfortunately, we were plagued with narrow bands of cirrus clouds that seemed to park themselves in between us and our target. These were barely perceptible to the naked eye, but they affected at least 25% of my subs over the course of the night.
Equipment
Astro-modified Canon 7D mkii camera, Askar ACL200 200mm f/4 lens (260mm focal length equivalent), Fornax LighTrack II tracking mount without guiding on a William Optics Vixen Wedge Mount. QHYCCD Polemaster. Gitzo CF tripod, Canon shutter release cable, laser pointer to help find Polaris and sky targets, lens warmer to prevent dew and frost on lens, dummy battery to power camera, lithium battery generator to provide power to camera, dew heater and laptop computer.
Imaging Details
Lights taken (ISO 2000, f/4, 120 second exposure): 153
Lights after cull due to tracker error, wind, bumps, clouds, etc.: 131
Used best 90% of remaining frames for stack for a total of 118 subs used for integration (3h 56m)
Calibration frames: none
Processing
RAW files converted to TIF in Canon DPP, stacked in Astro Pixel Processor, GraXpert for gradient removal, Starnet++ for separating nebulas from stars, Photoshop CS6 for stretching and other cosmetic adjustments.
Problems and learnings
I know this section has just turned into a bitch session and this night was a bit on the rough side as well. First, I was disappointed in myself for the time it took to properly compose the target. Finding the object wasn’t too difficult, but because of the faintness of the targets, I just couldn’t get my mind together to make this tight framing (this image is only slightly cropped). After wasting nearly two hours of dark skies on getting the final composition and then having to do a second polar alignment (I think I must have nudged the tripod while making composition adjustments), I was finally taking images.
Next the periods of clouds. I continued to let the camera go even though I knew I would be tossing some frames. I culled about 20 frames due primarily to clouds but I left another 20 or so in the stack that I thought wouldn’t hamper the final result.
Typically, I can arrange the rig and counterbalance bar so that I do not require a meridian flip. I guess in my frustrations in finding and composing, I neglected to think about this. Yep, somewhere around midnight, I realized the camera was going to be running into the tracking unit if I didn’t perform this flip. Of course, doing this manually, meant I had to go through the process of finding and composing the target again! This time didn’t take me nearly as long and I was back to shooting in about 40 minutes or so.
All of the above explains why I was only able to collect about half of the data that I should have been able to on a night like this. The clouds got bad enough towards the end of the night that I shut down with more than an hour of usable night left.
Conclusion
With the challenges on this night, I guess I have to be satisfied that I have something to share. This is another popular target that most astrophotographers get to pretty early. November is by far the best month for this target as it is viewable from the beginning to the end of night. There are a few other compositions to consider here, like shooting each nebula separately, or even focusing in on the heart of the heart – Melotte 15. So, I definitely have reason to revisit this section of the night sky someday.
A Thousand Acres of Silphiums 
Bill I am very happy how you captured and composed this. Given everything, you came out ontop with useable data.
Thanks a lot, Miguel. It pales in comparison with your versions, but it’s what I do. And it was still a great evening.
Although we are using different tools, we are still able to produce exceptional images that we can take pride in. I believe that our diverse approaches can lead to even more creativity and innovation in our work.
What kind of wavelength of light is this photographed in?
Hi Cate. This was photographed using visible wavelengths with an astromodified dSLR camera. The camera sensor has the IR filter removed in order to pick up far red and near IR radiation.