Mz 1 (Menzel 1), is a relatively bright mag 12 bipolar planetary nebula in the constellation Norma at a distance of 3400 light-years.
Mz 1 was discovered in 1922 by Donald Menzel with a 24 inch telescope.
It has a prominent central ring of enhanced emission. One model of its structure is a three-dimensional hour-glass shape with a smoothly decreasing density starting from the waist or equator as measured outwardly to the poles. It is radially expanding at a rate of about 23 km/s and estimated to be around 4,500 to 10,000 years old. Its apparent dimensions are 80 x 39 arc-sec.
Image data:
HaO3RGB (440-360-100-100-100 min) total 18.3 h, north is up, seeing 0.8-1.3 arc-sec,
80cm f/7 Astrooptik Keller cassegrain, FLI PL-16803, Astrodon filters, Prompt 7 CTIO Chile
Processing: Johannes Schedler
See the Ha-OIII-RGB image below in 100/200% size and a stretched version at bottom