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Old 12-08-2018, 06:19 PM
Tropo-Bob (Bob)
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Join Date: Sep 2013
Location: Cairns
Posts: 1,584
My observations

I observed these on the evening of 10th August. Most were observed with my Orion 80mm Triplet, however, I used my Meade 127mm ED , F9 for the planetaries.


Objects of interest

Rho Aquilae. Because of its relatively high proper motion, Rho crossed the border from Aquila into Delphinus in 1992.

I saw this white star, which was just visible to the unaided eye. It was more of a curiosity than a serious observation. Nevertheless, it made me again think of humans have constructed the constellations and that the stars within them are not bound to follow our rules!


NGC 6981. The Blue Flash Nebula (Planetary Nebula)
A blue , little Oasis in the middle of a field of very faint stars. Nicely seen with the 10mm Radian (114x). I had great difficulty star hopping to this one. The problem was only solved with I put the scope on Eta, and moved the EQ mount to the appropriate area.


NGC 6905. Planetary Nebula
The Planetary did not look like a typical planetary. It appeared as an ill defined, colourless patch, near a bright star. The star was brighter than the nebula and this made it hard to determine details.

Strangely, the Planetary had size and was visible even with my Parks 35mm (32x). Initially it looked rectangular, but as my eyes adapted to overcome the distraction of the bright star, it looked more round. Higher magnifications helped, but not as much as they normally do. If I had not already known its identity, I could have believed that this faint patch was a galaxy, a faint globular or just an ordinary nebula.


Struve 2725. Called the "Ghost Double", is a pair that appears similar to Gamma, but dimmer. Its components of magnitudes 7.6 and 8.4 are separated by 6 arcseconds and are 15 arcminutes from Gamma Delphini itself

Split with 32x and the pair looked about a magnitude different in brightness. They were a nice sight and were easily in the same field as Gamma when using the 80mm.


Struve 2690. Double in the same field as Epsilon Del. Mags 7.1 & 7.4 with a separation of 17.3 arc seconds.

A pair of near equal stars that were split with 20x, but looked better with 32x



The Main Stars

The four stars Alpha to Delta are an asterism nambed Job's Coffin.
These were easily visible to the eye. Epsilon was also visible, a short distance away.

Alpha Delphini (Del). Sualocin. 250Lys away.
Appeared white.

Beta Del. Rotanev. A close binary (separation 0.6")
Appeared Lemon-White.


Gamma Del. Fine binary with a period of 3,000 years.
This binary pair is well known for its contrasting colours. The primary looked Gold, but I was uncertain of the secondary, though it was very plainly a different hue. I settled on a royal blue.

The pair was easily split with 32x and appeared to be less than a magnitude different in brightness.


Delta Del. A spectroscopic binary.
It looked white, perhaps lemon white.

Epsilon Del. 330 Lys away.
Appeared white.
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