M27, also called the Dumbbell Nebula or Apple Core Nebula, is a planetary nebula – the gases expelled from a red giant star before it becomes a white dwarf, lit up by that star.  It’s located in the Milky Way, approximately 1250 light years away, and it has an apparent size of 8 arcmintues, making it 2.9 light years across.  It’s estimated to be 12,700 years old.

Planetary nebulae do not last long on an astronomy time scale because the expelled gases grow dimmer as they expand away from the central star.  I am glad I live in a time when we can observe them and they can be observed!

Planetary nebulae were originally called that because they looked like a round (like a planet) ball of fuzz by visual observers.  However, now we know they have nothing to do with planets and are actually shell(s) of gas expelled from a red giant star.  With astrophotography, we can pick up so much more detail than a fuzzball, and so we end up with interesting names.  For this nebula, some thought the inner core of this nebula looked like a dumbbell; others thought it looked like an apple core.  With the outer fringe, what do you think it looks like?

I used data from my driveway in Friendswood, Texas with suburban Bortle 7 – 8 brightness skies (lots of light pollution) to make this image.  In order to capture the outer fringe I needed a lot of data: 12.2 hours of Ha data and 10.65 hours of Oiii data, taken over nine nights.

This is a narrowband image, mapping Oiii to blue and Ha to red.  My goal was to capture both the details in the core and the outer fringe.  It took three processing tries, but I think I was ultimately successful.

Isn’t our galaxy beautiful?

Camera geek info – Narrowband:

• Williams Optics Zenith Star 73 III APO telescope
• Williams Optics Flat 73A
• ZWO 2” Electronic Filter Wheel
• Antila HO filters
• ZWO ASI183MM-Pro-Mono camera
• ZWO ASiair Plus
• iOptron CEM40
• Friendswood, Texas Bortle 7-8 suburban skies

Frames:

• June 22, 2024
  • 20 60 second Gain 150 Ha lights
  • 30 0.05 second Gain 150 Ha flats
• June 28, 2024
  • 47 60 second Gain 150 Oiii lights
  • 30 0.05 second Gain 150 Oiii flats
• July 3, 2024
  • 100 60 second Gain 150 Ha lights
  • 30 0.05 second Gain 150 Ha flats
• August 15, 2024
  • 256 60 second Gain 150 Oiii lights
  • 30 0.05 second Gain 150 Oiii flats
• August 16, 2024
  • 283 60 second Gain 150 Ha lights
  • 30 0.05 second Gain 150 Ha flats
• August 20, 2024
  • 45 60 second Gain 150 Oiii lights
  • 30 0.05 second Gain 150 Oiii flats
• August 22, 2024
  • 136 60 second Gain 150 Oiii lights
  • 30 0.05 second Gain 150 Oiii flats
• August 23, 2024
  • 155 60 second Gain 150 Oiii lights
  • 30 0.05 second Gain 150 Oiii flats
• August 24, 2024
  • 327 60 second Gain 150 Ha lights
  • 30 0.05 second Gain 150 Ha flats
• 30 Flat Darks from library
• 30 Darks from library

Processing geek info:

• PixInsight
• BlurXterminator
• NoiseXterminator
• StarXTerminator
• Generalized Hyperbolic Stretch
• NBColourMapper