| Emission nebula | |
|---|---|
| Planetary nebula | |
) 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] |
| Constellation | Cygnus |
| Physical characteristics | |
| Radius | 0.22 x 0.20[2] ly |
| Designations | HD 186924, SAO 31951,[1] Caldwell 15 |
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]
See also
- List of NGC objects
- Planetary nebulae
References
- ^ a b c "NGC 6826". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2007-04-17.
- ^ a b c "NGC 6826". Stellar Scenes Image Collection. Retrieved 2007-10-05.
- ^ "NGC 6826 : The Blinking Nebula". astroimages.org. Retrieved 2007-10-05.
External links
- "Hubble's planetary nebula gallery. A view of NGC 6826". Hubble Space Telescope.
- NGC 6826 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images