Hb 12

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Planetary nebula
Hb 12
Photo from the Hubble Space Telescope
Photo from the Hubble Space Telescope
AladinLite
Position
equinox : J2000.0
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

  1. http://vizier.u-strasbg.fr/viz-bin/VizieR-S?PN%20G111.8-02.8
  2. a b Sun Kwok, Chih Hao Hsia: Multiple Coaxial Rings in the Bipolar Nebula Hubble 12 , bibcode : 2007ApJ ... 660..341K
  3. NMH Vaytet et al .: High-speed knots in the hourglass shaped planetary nebula Hubble 12 , arxiv : 0905.4625