Introduction by Martin Griffiths. I very much appreciate that he provided this quote specifically for this image post:

“Observing Planetary Nebulae has been a passion of mine since a young age. These ethereal gaseous outflows are all that is left of sun like stars at the end of their lives and are a salutary lesson for our future in that nothing lasts forever. The Griffiths Planetary List was an idea that came to me as I enjoyed looking at these objects and wanted to share the best with other observers. Gary Imm’s beautiful images of each nebula on the list are wonderful examples of his dedication and expertise. I hope that generations will enjoy these lovely images and keep them in mind as they observe the Griffiths Planetary List”.

Martin Griffiths BA BSc MSc FRAS FHEA

Astronomer

Director, Brecon Beacons Observatory

Dark Sky Wales

*****************************************

Planetary nebulae (PN) are wonderfully unique and beautiful objects to view and image. Although some PN have been included on other famous lists such as Messier and Caldwell, the first PN-focused list (to my knowledge) was developed fairly recently by Martin Griffiths in his excellent 2012 book, “Planetary Nebulae”. The Griffiths Planetary List consists of 45 non-Messier PN ranging from +82 to -24 declination. In his words, he picked these PN “to strike a balance between brightness, size and observability by concentrating on exciting and challenging nebulae that the author has personally seen in almost 40 years of examining the skies. Purposely ignored are the 4 Messier PN objects.” Like the Messier and Caldwell lists, this list was developed primarily for eyepiece viewing, but all of the objects on these lists make great astrophotography targets as well.

On my poster, the objects are listed in order of GPL number from top left to bottom right. Griffiths numbered them in increasing RA value. I have shown each PN roughly to scale. Each PN image is accompanied by its primary designation, common nickname (if there is one), size (in arc-seconds and light years), magnitude, distance (in thousands of light years), and declination.



PN technical data is a challenge to determine and varies from source to source. I sourced the size information from my image, which often resulted in diameters which were quite larger than those listed in Griffith’s book. Perhaps that is because my images capture larger areas of extent, such as outer rings, which were not visible to Griffith. The magnitude information is from Griffith’s book, and the distance information is from various sources.

I tried to also include the surface brightness. But that data varies tremendously from source to source, and I came to the conclusion that surface brightness for these unusual objects is not a reliable parameter because of the wild brightness fluctuations across each object.

As with my other posters, contact me at [email protected] if you would like a spreadsheet of this data. This poster and individual object images are contained in my Griffiths Planetary List collection.

A few comments about this list:

- NGC 6857 was originally thought to be a planetary nebula. But starting in 1970, the view developed that it an HII region and not a PN. In my opinion, the detail of my image of this object confirms that it is not a PN, since the structure is unlike any PN that I have seen. Also, its size of 11 light years is too large for a bright PN, and its distance of 30,000 light years is beyond the furthest PN by about a factor of 2. But I respect Griffiths’ expertise, so I kept this entry in the list.

- No Abell PN made the list. That is because they are generally too dim for eyepiece viewing.

- There are 5 nice PNs a bit further south, ranging from -34 to -40 degrees declination: NGC 2818, NGC 3132, NGC 6302, NGC 6337, and NGC 6563. If your imaging location can reach these PNs, they are better objects than many on this list.

The GPL objects are listed below. As earlier stated, the GPL list is numbered by right ascension value:

1. NGC 40

2. NGC 246

3. IC 289

4. IC 2003

5. NGC 1501

6. NGC 1514

7. NGC 1535

8. IC 418

9. NGC 2022

10. IC 2149

11. HD 44179

12. NGC 2346

13. NGC 2371

14. NGC 2392

15. NGC 2438

16. NGC 2440

17. NGC 3242

18. NGC 4361

19. IC 3568

20. IC 4593

21. NGC 6210

22. NGC 6309

23. NGC 6369

24. NGC 6445

25. NGC 6543

26. NGC 6572

27. NGC 6741

28. NGC 6751

29. NGC 6781

30. NGC 6804

31. NGC 6818

32. NGC 6826

33. NGC 6857

34. NGC 6891

35. NGC 6894

36. NGC 6905

37. NGC 7008

38. NGC 7009

39. NGC 7026

40. NGC 7027

41. NGC 7048

42. NGC 7139

43. NGC 7293

44. IC 5217

45. NGC 7662

For completeness, I have completed another poster here which includes all 45 of the above GPL objects, plus the 4 Messier PN, plus the 5 southerly PN, for a total of 54 bright planetary nebulae.

If you would like to access all my DSO compilation posters, please click here.