Rings and jets around PSR J2021+3651: The Dragonfly Nebula

describe recent Chandra ACIS observations of the Vela-like pulsar PSR J2021+3651 and its pulsar wind nebula (PWN). This Dragonfly Nebula displays an axisymmetric morphology, with bright inner jets, a double-ridged inner nebula, and a similar to 30 '' polar jet. The PWN is embedded in faint diffuse emission: a bow shock-like structure with standoff of similar to 1' brackets the pulsar to the east and emission trails off westward for 3'-4'. Thermal (kT(infinity) = 0.16 +/- 0.02 keV) and power-law emission are detected from the pulsar. The nebular X-rays show spectral steepening from Gamma = 1.5 in the equatorial torus to Gamma = 1.9 in the outer nebula, suggesting synchrotron burnoff. A fit to the Dragonfly structure suggests a large (86 degrees +/- 1 degrees) inclination with a double equatorial torus. Vela is currently the only other PWN showing such double structure. The similar to 12 kpc distance implied by the pulsar dispersion measure is not supported by the X-ray data; spectral, scale, and efficiency arguments suggest a more modest 3-4 kpc.