ROSAT PSPC (0.1–2.4 keV) image of the IC 443 region. The overlaid black contours represent the bright optical filaments. The explosion sites from 0 to 30 kyr are shown as a white cone. The geometrical center is denoted by a white cross, and the NS is denoted by a white circle. The SNR lies in a complex region together with SNR G189.6 + 03.3 and H II regions. However, its true extent toward the east-southeast is probably significantly larger, and the explosion sites we found are closer to the real geometrical center.