NGC 6826 is a magnitude +8.8 planetary nebula located in northeastern Cygnus. It's a compact object that blinks on and off when observed, hence the name Blinking Planetary. Most planetary nebulae exhibit this type of behaviour but with NGC 6826 it's particularly obvious. When you look directly at the central star the nebula tends to fade away but glancing towards the edges - using averted vision - it suddenly re-appears. Switching back and forth rapidly between averted and direct vision causes the nebula to dramatically blink on and off.

NGC 6826 was discovered by William Herschel on Sep 6, 1793. It's number 15 in the Caldwell catalogue and is best seen from northern locations during the months of June, July, August.

NGC 6826 (credit:-  NASA, ESA, and The Hubble Heritage Team (STScI/AURA))

The Blinking Planetary is positioned 11 degrees northwest of Deneb (α Cyg - mag. +1.25) and 1.35 degrees east of theta Cyg (θ Cyg - mag. +4.5). It can be seen with popular 7x50 or 10x50 binoculars, although it appears only like a dim star. Through a small scope, such as an 80mm (3.1-inch) refractor, NGC 6826 appears evenly illuminated but small. The main section of the nebula spans just 27 by 24 arc seconds and is therefore smaller than the apparent diameter of the planet Jupiter. However, it responds well to power and the magnitude +10.6 central star is easily visible. Within a degree of NGC 6826 is double star 16 Cyg, consisting of two white 6th magnitude stars.

Through a 200mm (8-inch) scope NGC 6826 appears bright and blue-green in colour. High magnifications of the order of 250x display an elongated shelled structure. With direct vision the central star is prominent but averted vision brings out the nebula and at the same time reducing the dominance of the star. A nebula filter like an Olll helps increase the visibility of the disk but tends to dim the central star. With large backyard scopes the planetary is well defined and the blinking effect obvious.

Finder Chart for NGC 6826 (credit:- freestarcharts)

Finder Chart for NGC 6826 - pdf format (credit:- freestarcharts)

NGC 6826 is estimated to be 2,200 light-years distant. There is deal of uncertainty about this figure and it could be as close as 2,000 light-years or as far away as 5,000 light-years. The Hubble Space Telescope spectacularly imaged it revealing two bright patches on either side, which are known as Fast Low-Ionization Emission Regions, or FLIERS. They appear to be relatively young, moving outwards at supersonic speeds.

NGC 6826 Data Table

NGC6826
Caldwell15
NameBlinking Planetary
Object TypePlanetary Nebula
ConstellationCygnus
Distance (light-years)2,000 -> 5,000
Apparent Mag.+8.8
RA (J2000)19h 44m 48s
DEC (J2000)50d 31m 31s
Apparent Size (arc secs)27 x 24 (main section)
Radius (light-years)0.25 -> 0.65
Notable FeaturesHas a bright central star at mag. +10.6

Sky Highlights - March 2017

Comet
Comet 41P/Tuttle-Giacobini-Kresak now visible with binoculars as it heads towards perihelion

Mercury
Mercury heading towards greatest elongation east

Minor Planet
Vesta now visible with binoculars and small telescopes.

The Planets
This Month's Guide

Algol Minima
Algol eclipse dates and times for March 2017

Northern Hemisphere
Evening
West:- Venus (mag. -4.8 to -4.1 - first half of month), Mars (mag. +1.3 to +1.5), Uranus (mag. +5.9), Mercury (mag. -1.5 to -0.4 - second half of month)
Midnight
Southeast:- Jupiter (mag. -2.3 to -2.5)
Morning
Southwest:- Jupiter
Southeast:- Saturn (mag. +0.5)

Southern Hemisphere
Evening
West:- Venus (first half of month), Mars, Uranus
Midnight
North:- Jupiter
East:- Saturn
Morning
West:- Jupiter
Northeast:- Saturn
East:- Neptune (mag. +8.0 - second half of month)

Deep Sky
Naked eye / binoculars:-
Melotte 111 - Mel 111 - The Coma Star Cluster (Open Cluster)
Messier 44 - M44 - The Praesepe (Open Cluster)

Telescopes:-
Messier 67 - M67 - Open Cluster
Messier 51 - M51 - The Whirlpool Galaxy (Spiral Galaxy)
Messier 97 - M97 - The Owl Nebula (Planetary Nebula)
Messier 101 - M101 - The Pinwheel Galaxy (Spiral Galaxy)
Messier 65 – M65 – Spiral Galaxy
Messier 66 - M66 - Intermediate Spiral Galaxy
Messier 95 - M95 - Barred Spiral Galaxy
Messier 96 - M96 - Intermediate Spiral Galaxy
NGC 4244 - Spiral Galaxy
NGC 4565 - Needle Galaxy - Spiral Galaxy

Shop at Amazon US

Shop at Amazon US

Current Moon Phase

CURRENT MOON

Contributions

If you like the website and want to contribute to the running costs then please do so below. All contributions are most welcome.