Archive for September 23, 2022

NGC 6751 Planetary Nebula In Aquila: September 2022 Observer’s Challenge Object: #164

September 23, 2022

Work-File: Used only for organization and editing. When all entries are received by (October 8th) a final .pdf report will be issued by the 10th, and at that time will be posted on this page.

Bertrand Laville: Observer from France

Object information
Object name:NGC 6751
Object type:Planetary Nebula
Right Ascension:19h 05m 59s
Variation:05° 59′ 48″ S
Observations Details
Date of sighting:Jul 20, 2001 11:00 PM UT
Duration of observation:30 mins
Object position:Alt: 39.3°, Az: 184.4°
Weather conditions :not related
Observation conditions:T1, P2
Viewing location:Chabottes-les-Auberts
Instrument :TSC LX200/254 Meade
Main eyepiece:Televue Radian 10mm
T254x105 Meade SWA 24.5mm without filter

The NP is identified by blinking!x105 Meade SWA /OIIIThe NP is luminous NP, m~11v, not 12v, as indicated by Guide7, round, bluish, D<30″x185 Meade SWA 13.8mm without filterAll the stars were positioned at this G, and without Guide7. In VI, the center of the NP appears much darker (see drawing)x185 Meade SWA 13.8mm/OIIIThe diameter of the NP increases, but the central hole disappears; the round outer shape is not certain, and has irregularities x254 Radian 10mm without filterThe NP is seen V2, obvious, round, obvious annularity. Darker center, d ~1/3 to 1/4 of D (D = 30″). CS* was suspected but not sure

T635 Date of sighting: Sep 29, 2011 7:30 PM UTDuration of observation: 

72 minObject Position: Alt: 36.6°, Az: 204.5°Weather conditions: 3 p.m.: D++ V1/R15kmh t25° hu35% T2-3 9:15 p.m.: N++ V0 t16° hu49% QZ21.37MWCyg L60N21.35Observation conditions: SQMZ 21.37(MWCyg) SQML(60°N) 21.35 FWMH 1.5″ mvlon(UMi) 5.8/VI4-5 T3 P3 S4/520 5/890Place of observation: Observatory of the Baronnies ProvençalesInstrument:

TN 635 Dobsonian ObsessionMain eyepiece: Televue Nagler 3.5mm Type 6Magnification: 

890×101 Nagler 31mmThe field is easy to find, but it is so rich that the NP gets lost in it. 

Nevertheless, when found, it is obvious albeit small. Very pale blue, C130/S10-15.x520 Ethos 6mmI start as usual to position the nearby stars, in yellow on the Youman image. The CS* is almost prominent.x890 Nagler 3.5mmAlthough the seeing is quite strong, it is the best G to analyze the NP. 

The HST image helps well to understand the Youman image. The 3 bananas, L5, are difficult, but safe. That at N is the most concentrated; that to the SE is the most important, and both deform the perfect circle of the NP. I did not perceive the straightness of the N edge, and the banana there is the most difficult of the three.The central hole is well seen, but low in contrast, small, d ~ D/3, and almost entirely filled by the CS*, m ~ 15v.Like all the NPs imaged by the HST or the Gemini, or any other large diameter, we are a little disappointed: while we are expecting fireworks, we only see a ring of smoke third grade![Note 2020 07: as often, I made the mistake of detailing the NP only at high magnification. And so, I neither looked for nor perceived the halos, internal bilobed, and external round, clearly visible on the Gemini image.]

Mario Motta: Observer from Massachusetts

The following image was taken with my 32-inch scope and with a ZWO ASI 6200 camera, 1 hour of H alpha, and O3 filter, 40 min S2 NB imaging. 

I also took 50 minutes of luminance filter to obtain the central star and surrounding stars.

Combined in PixInsight.

Phil Orbanes: Observer from Massachusetts

Attached is my photo of planetary NGC 6751, the Glowing Eye Nebula, in Aquila, which lies about 6,500 light years away.

It  was a very difficult object for me due to its small size.  I use a 14-inch Planewave reflector with a focal reducer.  The image provided is an enlargement of what I obtained.

Taken with an FLI 16803 CCD camera, the 18 hours of exposure time was divided evenly between R, G, B, Ha and O3 filters.

NGC 6751 is a complex bipolar planetary nebula.  The inner bubble” shows up pretty well in my photo, but its outer hydrogen halo is very dim, which can be partly seen if you look closely.

Roger Ivester: Observer from North Carolina

Dates: August 1st and 14th 2022

Telescope: 10-inch f/4.5 Equatorial Reflector 

Eyepieces: 11mm + 2.0x Barlow 

Sketch Magnification: 208x 

Field of View: 0.39º 

NELM: 4.7 

Location: Suburban backyard with moderate light pollution.

Description: Very small, mostly round, featureless, with the central star being visible, but only at higher magnification. 

Michael Brown: Observer from Massachusetts

NGC 6751 is a small, faint planetary nebula in Aquila.  I’ve always found it interesting to compare the many planetaries in that area of the sky.  This one, while faint, is definitely visible in my 8-inch SCT with direct vision.  I am not able to discern any significant detail, such as any variation in brightness between inner and outer locations.  I may have had brief glimpses of the central star with averted vision, but I cannot be sure I really saw it.  

In spending more time than usual studying this nebula (this is the Challenge Object of the Month, after all!), I noticed that averted vision is most effective when I look to the right of, and to a lesser extent below, the object.  That presumably indicates which areas of my retina are most sensitive.

I slewed to the northwest of the nebula to see the nearby carbon star V Aquilae.  The red color was readily apparent.

I captured NGC 6751 and V Aquilae in a photograph.  This was taken with my Canon T1i digital SLR camera, 8-inch scope at F6.3, 26 minutes total exposure.  The tiny bluish “dandelion puff” with the central star is at center, and V Aquilae is at upper right.