PK238+34.1 or Abell 33 (Also called A33 or the Diamond ring nebula) is a faint spherical planetary nebula located 2700 light years away in the constellation of Hydra. It lies just behind the star HD 83535 which has no relation to the nebula.[1] The star HD 83535 is also responsible for the "diamond ring" effect seen in the photograph.
The nebula gets its coloration from the O III emissions (doubly ionized oxygen). The nebula is faint making it difficult to be seen using a telescope. The spherical shape of Abell 33 is mainly caused by its central star not having much of a spin.[2] The nebula shares similar morphology to another nebula with the same spherical shape, the Owl Nebula (M 97), but is much darker than the Owl Nebula.[3]
There is also a galaxy cluster known as Abell 33, because there are two Abell astronomical catalogs, one for planetary nebulae, and one for galaxy clusters.
| Object | PK238+34.1 Diamond Ring Nebula |
| Constellation: | Hydra |
| Position: | RA 09h 39m 09s Dec 02° 48' 31'' RA -05 48 31 |
| Apparent Size: | 4 arcmins |
| Apparent Magnitude: | 12.9 |
| Distance in light years: | 2700 ly |
| Photo Data | |
| Date: | 04 Jan 2025 - 11 Jan 2025 |
| Location: |
El Sauce Observatory Chile (1525m ASL) GPS: 30.472529° S, 70.762999° W |
| Telescope: | CHI-1-CMOS: Planewave CDK24 610 mm, f/d 6.5/3962mm |
| Camera: | QHY 600M Pro, 3.76μm, 9576 x 6382px, Bin-2 4788x3191px, @ T sensor = -10°C |
| Field of View: | 31x21 arcmins |
| Pixel Scale/Resolution: | 0.39 arcsec/px |
| Expose frames/times: | L 26x300s, R 26x300s, G 26x300s, B 26x300s = |
| Total expose: | 8h 40min |
| Filter: | Astrodon Luminance, Red, Green, Blue |
| Mount: | Mathis MI-1000/1250 with absolute encoders |
| Software: | Siril 1.4, Photoshop CC |
| Remarks: |
© Photos and photo data by Peter Cerveny
© Object description/intro text fully or partially by Wikipedia,
which is released under the Creative Commons Attribution-ShareAlike 4.0 International License