NGC 5189 is an intriguing Planetary Nebula (PN) in the constellation of Musca. It is also known as Gum 47, IC 4274 and the Spiral Planetary Nebula. I haven't imaged many PNs to date. They are often quite small objects and even with my 2.8m focal length, substantial cropping is required. Revision B shows this object in my normal FOV (0.75 degree square), where it is set in the rich star field of the Milky Way and is quite far south with Celestial Coordinates of RA 13h33m36.02s, Dec -65°58'48.64". It has a reported long axis dimension of 2 light years, corresponding to 3.36 arc mins as estimated from my wide field image and consistent with its reported distance of some 2000 light years. Other measurements put it at more like 3000 light years distant, which, if true, would make it 3 light years across.

It is bright in Ha (the red colour), OIII (the blue-green colour) and SII (also red). I have captured narrowband (SHO) data which I will process in due course. I will also use the NB data to enhance this LRGB image.

NGC5189 was discovered by James Dunlop on 1 July 1826, who catalogued it as Δ252. For many years, well into the 1960s, it was thought to be a bright emission nebula. It was Karl Gordon Henize in 1967 who first described NGC 5189 as quasi-planetary based on its spectral emissions. Seen through the telescope it seems to have an S shape, reminiscent of a barred spiral galaxy. The S shape, together with point-symmetric knots in the nebula, have for a long time hinted to astronomers that a binary central star is present. The Hubble Space Telescope imaging analysis showed that this S shape structure is indeed two dense low-ionization regions: one moving toward the north-east and another one moving toward the south-west of the nebula, which could be a result of a recent outburst from the central star. Observations with the Southern African Large Telescope have finally found a white dwarf companion in a 4.04 day orbit around the rare low-mass Wolf-Rayet type central star of NGC 5189. NGC 5189 is estimated to be 546 parsecs or 1,780 light years away from Earth. Other measurements have yielded results up to 900 parsecs (~3000 light-years).....courtesy Wikipedia.

The mouse over to Revision C shows a zoomed in view of the PN.

The structure visible in the nebula compares very favourably with the Hubble Space Telescope image and is a testament to the efficacy of RC-Astro's BlurXTerminator.