Celestial hemisphere:  Northern  ·  Constellation: Gemini (Gem)  ·  Contains:  NGC 2395  ·  PK205+14.1  ·  Sh2-274
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Abell 21 - Medusa Nebula, Paul Ricker
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Abell 21 - Medusa Nebula

Getting plate-solving status, please wait...
Abell 21 - Medusa Nebula, Paul Ricker
Powered byPixInsight

Abell 21 - Medusa Nebula

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Description

Abell 21 (Sh2-274), the Medusa Nebula, is a planetary nebula about 460 pc away and ~ 2 pc across. Planetary nebulae are the ejected envelopes of low-mass stars whose cores are shutting down and becoming white dwarfs; they fluoresce due to UV radiation produced by the core, which has a temperature > 50,000 K. In this case the central star, PNG 205.1+14.2, is a "PG 1159 star," which is not quite done fusing helium in its outermost layers. Nearby is the loose open cluster NGC 2395.

Registered and stacked in Astro Pixel Processor, stars extracted using the new version of StarNet++, edited and combined in Photoshop, then used the Heal tool in StarTools to clean up the star shapes. A few final tweaks in Photoshop Elements.

Image produced from exposures taken at the Casitas de Gila guest houses in SW New Mexico.

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Abell 21 - Medusa Nebula, Paul Ricker