Celestial hemisphere:  Northern  ·  Constellation: Gemini (Gem)  ·  Contains:  NGC 2395  ·  PK205+14.1  ·  Sh2-274
Getting plate-solving status, please wait...
Abell 21, Kirby Collins
Powered byPixInsight

Abell 21

Getting plate-solving status, please wait...
Abell 21, Kirby Collins
Powered byPixInsight

Abell 21

Equipment

Loading...

Acquisition details

Loading...

Description

Abell 21 is a faint planetary nebula in the constellation Gemini, discovered by George Abell in 1955.  

The Medusa Nebula is about 1500 light years away, and over 4 light years across.  Scientists originally thought it might be a supernova remnant, but later studies identified it as a planetary nebula (shells of gas emitted by a late stage star).

I used the Ha data as luminance to show structure.

Comments

Sky plot

Sky plot

Histogram

Abell 21, Kirby Collins