A planetary in salmon pink colour

[Nyctimene]

Last evening, I visited for the second time "Campbell's Hydrogen Star" in Cygnus, rather close to Albireo, with the 18" Obsession. It's an unusual planetary, as it's tiny disc is glowing in reddish colour, not the usual blue or green of the OII emission lines. The colour derives from the planetary's emission lines in hydrogen, oxygen and carbon (have a look at the ESA link below). I started from Phi Cygni with mag 68 (30 mmf), still under murky 5.0 NELM/20.8 SQM-L skies; the planetary was visible after a short star hop as a not quite sharp star with a distinct salmon pink colour. Increasing the mag to 167x (Docter 12,5) showed a tiny coloured disc (7"), surrounding the 11 mag whitish central star. The suggested H beta filter increased the contrast to the background, but diminished the colour impression. Doubling the mag was without significant effect. The best view I had was with 227x (18 mmf+2x Barlow), without filter. -

The nice Delphinus globular 6934 was well resolved (not quite to the core) with 227x. Two faint 12.5/12.8 galaxy spindles at an angle of 90°, 1,3° S of Eta Del, 6928 and 6930, could be made out with direct vision, 6928 (SB type) with a bright, slightly oblong core region; the latter more diffuse. - Saturn was wobbly, the Cassini not visible.

The hydrogen star (in SkySafari to be found by it's PK number PK 64+5.1) should be in reach of medium scopes of 6-8"; so give it a go, and let us know" !

Added the link: https://esahubble.org/images/potw1337a/

Thanks for reading

Stephan

 

Edited September 1, 2022 by Nyctimene

[Cosmic Geoff]

Coincidentally I was trying to image the PK64+5.1 last night, and four nights ago, with a C8,  and to my frustration failed to see anything like it on screen or in the saved images. Nor could I establish whether I had been aiming at the correct field.

[Nyctimene]

1 hour ago, Cosmic Geoff said:

Coincidentally I was trying to image the PK64+5.1 last night, and four nights ago, with a C8,  and to my frustration failed to see anything like it on screen or in the saved images. Nor could I establish whether I had been aiming at the correct field.

I guess, that your aiming was off - with a total magnitude of 11.3, the central star of 10 or 11, it should be easy to capture it with 8". There is an E - W star chain of three stars,equally spaced, all around 10th mag, starting with V1744 Cyg, 34' W of Phi Cyg. Next is SAO 68544. The last in the chain is actually "Campbell's Hydrogen Star". Hth.

Stephan

Edited September 1, 2022 by Nyctimene

[Cosmic Geoff]

 

43 minutes ago, Nyctimene said:

I guess, that your aiming was off - with a total magnitude of 11.3, the central star of 10 or 11, it should be easy to capture it with 8". There is an E - W star chain of three stars,equally spaced, all around 10th mag, starting with V1744 Cyg, 34' W of Phi Cyg. Next is SAO 68544. The last in the chain is actually "Campbell's Hydrogen Star". Hth.

Stephan

A plate-solve in ASTAP confirms that the object was out of field - the GoTo being about 10' off target - not much, but enough to put it out of camera field.

[Captain Scarlet]

Thanks … my next target, skies permitting 

[bomberbaz]

I have looked at this a few times but never without the HB filter, I will try next time without it to see what colour I can tease out of it.