Astronomy:NGC 6826

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Short description: Planetary nebula in the constellation Cygnus


NGC 6826
Emission nebula
Planetary nebula
NGC 6826HSTFull.jpg
Hubble Space Telescope (HST) image of NGC 6826
Credit: HST/NASA/ESA.
Observation data: J2000 epoch
Right ascension 19h 44m 48.2s[1]
Declination+50° 31′ 30.3″[1]
Distance~2000 ly
Apparent magnitude (V)8.8[2]
Apparent dimensions (V)27″ × 24″[2]
ConstellationCygnus
Physical characteristics
Radius0.22 x 0.20[2] ly
DesignationsHD 186924, SAO 31951,[1] Caldwell 15
See also: Lists of nebulae
NGC 6826 "Blinking Eye".jpg

NGC 6826 (also known as Caldwell 15) is a planetary nebula located in the constellation Cygnus. It is commonly referred to as the "blinking planetary", although many other nebulae exhibit such "blinking". When viewed through a small telescope, the brightness of the central star overwhelms the eye when viewed directly, obscuring the surrounding nebula. However, it can be viewed well using averted vision, which causes it to "blink" in and out of view as the observer's eye wanders.

A distinctive feature of this nebula are the 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.[3]

The central star of the planetary nebula is an O-type star with a spectral type of O6fp.[1]

See also

References

External links