The Eskimo Nebula (NGC 2392) is a double-shell planetary nebula (PN) known for the exceptionally large expansion velocity of its inner shell, ∼90 km s-1, and the existence of a fast bipolar outflow with a line-of-sight expansion velocity approaching 200 km s-1. We have obtained XMM-Newton observations of the Eskimo and detected diffuse X-ray emission within its inner shell. The X-ray spectra suggest thin plasma emission with a temperature of ∼2 × 106 K and an X-ray luminosity of LX = (2.6±1.0) × 1031 (d/1150 pc)2 erg s-1, where d is the distance in parsecs. The diffuse X-ray emission shows noticeably different spatial distributions between the 0.2-0.65 keV and 0.65-2.0 keV bands. High-resolution X-ray images of the Eskimo are needed to determine whether its diffuse X-ray emission originates from shocked fast wind or bipolar outflows.Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.
Astronomy and Astrophysics
- Pub Date:
- January 2005
- ISM: planetary nebulae: general;
- ISM: planetary nebulae: individual: NGC 2392;
- stars: winds;
- 4 pages, 2 figures, accepted in Astronomy and Astrophysics Letters