Description
Ishida Weinberger 2 (IW2, PK 108+08) is a large, ancient, ellipsoidal planetary nebula (PNe) in the constellation of Cepheus, and is about 850 light years distant (Ishida and Weinberger, Astron. Astrophys. 178, 227—236, 1987). It appears to be slightly elongated in the NW-SE direction encompassing about 18.5’ (north is toward the upper right). The field is 32’ x 32’. From the expansion velocities of H-a and NII, IW 2 is estimated to have a kinematic age of about 40,000 years. It is quite faint but emits both H-a and NII, but no detectable OIII with our equipment. The effective temperature of its white dwarf star is 100,000 K. It is one of the largest PNe known, nearly 4 light years in extent. The filamentary structures are likely to be shock fronts due to the PNe interacting with the interstellar medium (Xilouris et al. Astron. Astrophys. 310, 603—612, 1996). This image includes 6.5 hours of 3 nm H-a and 5.5 hours of 3 nm NII data, with 1.25 hours of RGB data for star color. The H-a data were mapped to red and the NII data to magenta to keep the overall appearance as “natural”. This may be the only color image of IW2!
Exposure: 13.25 hrs Total: 6.5 hrs H-a, 5.5 hrs NII, 1.25 hrs RGB
Telescope: 16 in. RCOS RC f/8.9
Mount: Software Bisque Paramount ME
Oag: Astrodon MonsterMOAG
Acquisition: CCDAutoPilot4
Calibration: CCDStack2
Observatory Site: Sierra Remote Observatory, Shaver Lake, CA
Telescope: 16 in. RCOS RC f/8.9
Mount: Software Bisque Paramount ME
Oag: Astrodon MonsterMOAG
Acquisition: CCDAutoPilot4
Calibration: CCDStack2
Observatory Site: Sierra Remote Observatory, Shaver Lake, CA
Camera: Apogee U16M D09
Filters: Astrodon Gen2 RGB, 3nm H-a, NII
Guider: SBIG ST-402
Camera Operation: MaximDL5.18
Processing: Photoshop CS5
Image Date: 07/17/2011 - 08/20/2011
Filters: Astrodon Gen2 RGB, 3nm H-a, NII
Guider: SBIG ST-402
Camera Operation: MaximDL5.18
Processing: Photoshop CS5
Image Date: 07/17/2011 - 08/20/2011