Updated: May 18
NGC 2174 is an emission nebula in Orion. It is known as the Monkey Head Nebula due to its shape although it doesn't look obvious to us. Hmmm. Where is the monkey? 🙈🙉.
NGC 2174 is a great target for medium to large telescopes and is fairly easy to capture from the city using the right filters.
Object Designation: NGC 2174
Also known as: The Monkey Head Nebula
Object Type: Emission Nebula
Distance: 6,400 light-years away
Discovered in: Sometime before 1654 (cluster part)
To be honest, we never really cared that much about the Monkey Head Nebula. Don't get me wrong, it is a pretty object, but when compared to some of the other incredible Winter nebulae, we can say it doesn't stand out that much.
After spending a night imaging it though, I can say that I now like this target much more! zooming in on the object reveals some great intricate details where you can really see how the gases interact.
Looking at the target wide field is also interesting as you really get a sense of how huge space is due to the lack of any other object or gas anywhere around the huge Monkey Head. To put things into perspective, this target is larger than the full moon!
Another great aspect of NGC 2174 is the presence of an open cluster of stars embedded into the gases of the nebula, designated NGC 2175.
On the left is a close up image taken by the Hubble Space Telescope. You can see some of the bright stars forming the cluster
These stars can better be captured with a large telescope and surely would look fantastic if you are using a Newtonian.
The Monkey Head Nebula was the star of the 24th Hubble anniversary images in 2014. The photo attached is one of the four close up views NASA released that year.
The image shown the previous year was the Horsehead Nebula, which became
You can see all the images released for the Hubble anniversaries HERE.
The image below is the result of just one full night of imaging on the target. It was taken from our Bortle 9 backyard (Bortle 9) with 3nm narrowband filters.
NGC 2174 from our Bortle 9 backyard in narrowband
Telescope: Stellarvue SVX130
Mount: Paramount MyT
Guiding: ZWO ASI 290MM Mini
Accessories: Moonlite Nitecrawler focuser / Pegasus Astro Ultimate Powerbox
Power: Jackery Lithium Battery
Processing: PixInsight with RC-Astro Plugins
Total Exposure Time: 10 hours
Exposure Time per frame: 10 minutes
Filters: Chroma 3nm Ha/Sii/Oiii
How to find NGC 2174?
The Monkey Head Nebula can be found in the most popular constellation of the Winter sky: Orion.
First make sure to see the shape of the hunter, with his feet, his famous belt, his arms and his bow. NGC 2174 is located by the hand he has in the air, reaching for an arrow. It is by the extremity of the constellation very close to Gemini and Auriga borders.
It is not possible to spot the Monkey Head Nebula with the naked eye. We are not sure if you could potentially see it through a pair of binoculars as we haven't attempted it before but we do not believe you could, even under a very dark sky. The nebula is really faint and really pops out through astrophotography with the right filters.
Processing the Monkey Head Nebula
Processing the Monkey Head Nebula was fairly easy. I had issues with a reflection near the bottom of the image that is due to the incorrect back-focus distance between the sensor of the camera and the field flattener, but I was able to take care of it using the Clone Stamp process on the starless image. The starless image was created by using the StarNet process on PixInsight. You can learn how to activate and use it if you check out our tutorial!
The only tricky part was the bring out the colors in the outer edge of the nebula without blowing out the core. A small part in the center of the object is much brighter than all of the other gases.
If you are interested in learning how I process all our images, you can get our full PixInsight guide for Nebula below!
What did each single shot look like using the narrowband filters?
Below you can see what each single shot of the Monkey Head Nebula looks like for the three narrowband channels. We used the following filters to capture NGC 2174:
Hydrogen Alpha (left)
Sulfur II (center)
Oxygen III (right)
The Monkey Head Nebula is an object that never really excited us since we started Astrophotography. But imaging and processing this target was fun and it actually is a pretty nice nebula!
Have you captured the Monkey Head Nebula? Attach your image in the comments and let us know your acquisition details!