Showing posts with label Caldwell 4. Show all posts
Showing posts with label Caldwell 4. Show all posts

Sunday, June 11, 2023

Reflection in the Dark - The Iris Nebula

 It was a really good week for astrophotography!

Starting on the night of Sunday May 21st through Friday May 26, we had a great stretch of weather for astrophotography, at least as far as Western New York is concerned. Sunday and Monday were impacted by smoke from the wildfires in Alberta, Canada. Even with the smoke, I managed to capture data on SN 2023ixf in M101 (click here). Wednesday, Thursday, & Friday had better conditions. Being able to leave my scope setup all the way through Saturday (extremely rare for our area).

On Wednesday night I started the evening on SN2023ixf in M101 and then moved to another target (post coming soon) as I lose M101 in a tree around 1:30 AM. Not wanting to squander the clear skies I added a sequence for second target to NINA. Technically this was the morning of Thursday May 25th since it was after midnight. However, that's not how I think about it and organize my files. I started the imaging session on the night of Wednesday May 24th and carried that date through sunrise. That's the convention I follow, right or wrong. 

On Thursday, the Moon was setting around 1:30 AM. Thought I would try for the Iris Nebula. This target is something I've wanted to image for a while, but avoided as I considered it more of an "advanced" target. As my skills have been progressing, thanks to experience, mentors in the BAA, and knowledge/skill gained form Masters of PixInsight classes, I decided to give it a shot. glad I took the chance. On Friday I did not image M101, just felt like trying something different. I didn't want to go to the Iris right way because the Moon was brighter and wasn't going to set until 1:52 AM. So imaged another target (post coming soon) until 1:30 am and then switched back to the Iris. I think Thursday night was the best night of the week. 

The image was processed in PixInsight. It took multiple attempts to get this result, but I'm really pleased with it. Still a little unsure (due to inexperience with dust and dark nebulae surrounding the reflection nebula) I posted it on Twitter and asked for feedback. The feedback was very positive. I also shared the image with members of the imaging group within the BAA. Again, the feedback was positive. 

For the first time since I started imaging with this Deep sky setup, the hard drive on my imaging laptop was nearly full by the end of the week. Will need to consider upgrading the storage on the laptop. This was an unusual problem to have as we almost never get that many good nights so close together. It was a really fun week chasing the supernova in m101 and imaging the Iris and the other targets I went after. Very reminiscent of chasing Comet Neowise in 2020. I hope you enjoy the image.


The Iris Nebula (NGC 7023 / LBN 487) captured on 05/25/2023 & 05/26/23.

What is it?

The Iris Nebula is a fairly bright reflection nebula in the constellation of Cepheus. The reflection nebula is surrounded by lots of dust. The Iris Nebula is also known as NGC 7023, Caldwell 4, and LBN 487. Unlike emission nebulae, reflection nebulae do not emit their own light. The color comes from scattered light of its central star. Reflection nebulae are made up of very small particles, much smaller than dust particles on Earth. these particles scatter light giving the nebula its bluish color (similar to our sky).

An annotated image of the Iris Nebula and surrounding dust. 


How big is it?

It has an angular size of 18 x 18 arcminutes on the night sky and is about 6 light-years across. 

How far is it?

The Iris Nebula is within the Milky Way at about 420 parsecs (pc) or 1,400 light-years (ly) from Earth.

How to find it?

This object can be observed visually as well as being a popular photographic target. Dark skies are a must. 

Refer to the finder chart below. 

  1. Find Cassiopeia with its distinctive "M" or "W" shape.
  2. Find Polaris (the North Star).
  3. Find Cygnus or the Northern Cross. 
  4. The constellation Cepheus looks like a house and is located between items 1,2, & 3.
  5. The Iris Nebula is within the red box on the finder chart (the red box indicates the field of view of the image.
 

A finder chart for the Iris Nebula.

Image Details:

Capture Date:05/25/2023 and 05/26/2023
Location: Eden, NY
Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor
Camera: ZWO ASI2600MC Pro
Filter: None
Mount: Sky-Watcher USA EQ6-R Pro
Exposure: 5/25/: 60 exposures at 120 sec each; 5/26: 50 exposures at 120 sec each for a total exposure of 3.67 hours. Gain 100 / Offset 50 / -10°C for both nights.
Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!
Ernie





Follow

NGC 2237 - The Rosette Nebula (Skull Orientation)

This target was way too close to the nearly Full Moon ... The night of February 20th was just a few days before The Full Moon (2/24). Even w...