Hb 12
Planetary nebula Hb 12 |
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Photo from the Hubble Space Telescope | |
AladinLite | |
Position equinox : J2000.0 |
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Right ascension | 23h 26m 14.8s |
declination | + 58 ° 10 ′ 54.7 ″ |
Appearance | |
Central star | |
Physical data | |
history | |
discovery | Edwin Hubble |
Date of discovery | 1921 |
Catalog names | |
PK 111-02 1 • PN G111.8-02.8 • Hb 12 |
Hb 12 ( Hubble 12 ) is a planetary nebula discovered by Edwin Hubble in 1921 .
It has an hourglass shape with a multitude of knots that spread at a speed of 120 km / s. The planetary nebula is characterized by one of the highest surface brightnesses and has a ring-shaped structure that is believed to be formed every 50 years.
Web links
Individual evidence
- ↑ http://vizier.u-strasbg.fr/viz-bin/VizieR-S?PN%20G111.8-02.8
- ↑ a b Sun Kwok, Chih Hao Hsia: Multiple Coaxial Rings in the Bipolar Nebula Hubble 12 , bibcode : 2007ApJ ... 660..341K
- ↑ NMH Vaytet et al .: High-speed knots in the hourglass shaped planetary nebula Hubble 12 , arxiv : 0905.4625