The Medusa Nebula is a large planetary nebula in the constellation of Gemini on the Canis Minor border.
It also known as Abell 21 and Sharpless 274.
It was originally discovered in 1955 by UCLA astronomer George O. Abell, who classified it as an old planetary nebula.
The braided serpentine filaments of glowing gas suggests the serpent hair of Medusa found in ancient Greek mythology.

Until the early 1970s, the Medusa was thought to be a supernova remnant.
With the computation of expansion velocities and the thermal character of the radio emission, Soviet astronomers in 1971 concluded that it was most likely a planetary nebula.

As the nebula is so big, its surface brightness is very low, with surface magnitudes of between +15.99 and +25 reported.(WIKI)



S2-Ha-O3 image
Ha - 20X900 sec total of 5 HRS (BIN 1)
S2,O3 2 Hrs each (BIN 2)

Total of 9 HRS

Telescope - 8" F8 GSO RC (Carbon tube)
Mount - ASA DDM 60 PRO
NO GUIDING :)
Camera - SBIG ST8300M with BAADER filters.
Imaged from my home observatory in Gan-Yavne, Israel