{{Short description|Planetary nebula in the constellation Hydra}} {{Planetary nebula | image = Abell33s.jpg | caption = The Abell 33 [[nebula]] as seen from [[Mount Lemmon Observatory]] | epoch = [[J2000]] | ra = {{RA|09|39|09.2}} | dec = {{DEC|-02|48|35}} | dist_ly = 2.7 [[light year|kly]] (0.83 [[parsec|kpc]]) | name = Abell 33 | type = planetary | constellation = [[Hydra (constellation)|Hydra]] |notes = Foreground star gives it a "diamond ring" effect | names = PNG 238.0+34.8, PK 238+34.1, ARO 65 |appmag_v=+12.9}}
'''Abell 33''' (Also called '''A33''' or the '''Diamond ring nebula''') is a faint spherical [[planetary nebula]] located 2700 light years away in the [[Hydra (constellation)|constellation of Hydra]]. It lies just behind the star [[HD 83535]] which has no relation to the nebula.<ref>{{Cite web |title=Abell 33 Planetary Nebula in Hydra {{!}} Astrodonimaging.com |url=https://astrodonimaging.com/gallery/abell-33-planetary-nebula-in-hydra/ |access-date=2024-05-11 |language=en-US}}</ref> The [[star]] HD 83535 is also responsible for the "[[Engagement ring|diamond ring]]" effect seen in the photograph.
The [[nebula]] gets its [[color]]ation from the [[Doubly ionized oxygen|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.<ref>{{Cite web |title=Abell 33 – Astrodrudis |url=https://astrodrudis.com/abell-33/ |access-date=2023-10-27 |language=en-US}}</ref> The nebula shares similar morphology to another nebula with the same spherical shape, the [[Owl Nebula]] ([[Owl Nebula|M 97]]), but is much darker than the Owl Nebula.<ref>{{Cite web |title=Planetary Nebula Abell 33 {{!}} Deep⋆Sky Corner |url=https://www.deepskycorner.ch/obj/a33.en.php |access-date=2023-10-27 |website=www.deepskycorner.ch |language=en}}</ref>
There is also a galaxy cluster known as Abell 33,<ref>https://simbad.cds.unistra.fr/simbad/sim-id?Ident=abell+33&submit=submit+id</ref> because there are two Abell astronomical catalogs, one for planetary nebulae,<ref>https://en.wikipedia.org/wiki/Abell_Catalog_of_Planetary_Nebulae</ref> and one for galaxy clusters.<ref>https://en.wikipedia.org/wiki/Abell_catalogue</ref>
==References== {{Reflist}}
*http://www.caelumobservatory.com/gallery/abell33.shtml {{Webarchive|url=https://web.archive.org/web/20170512070210/http://www.caelumobservatory.com/gallery/abell33.shtml |date=2017-05-12 }} *http://www.skyhound.com/observing/archives/mar/A_33.html
==External links== * {{commons category-inline}}
{{Hydra (constellation)|state=collapsed}}
{{DEFAULTSORT:Abell 33}} [[Category:Planetary nebulae|Abell 33]] [[Category:Abell planetary nebulae|33]] [[Category:Hydra (constellation)]]
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