We present far-ultraviolet (FUV) spectral images, measured at C IV λ1550, He II λ1640, Si IV+O IV] λ1400, and O III] λ1664, of the entire Cygnus Loop, observed with the Spectroscopy of Plasma Evolution from Astrophysical Radiation (SPEAR) instrument, also known as FIMS. The spatial distribution of FUV emission generally corresponds with a limb-brightened shell, and is similar to optical, radio and X-ray images. The features found in the present work include a "carrot", diffuse interior, and breakout features, which have not been seen in previous FUV studies. Shock velocities of 140-160 km s −1 is found from a line ratio of O IV] to O III], which is insensitive not only to resonance scattering but also to elemental abundance. The estimated velocity indicates that the fast shocks are widespread across the remnant. By comparing various line ratios with steady-state shock models, it is also shown that the resonance scattering is widespread.

We present the results of far-ultraviolet (FUV) observations of the Monogem ring made with the FIMS/SPEAR instrument. The global map constructed from the C iv ll1548, 1550 emission lines presents clear evidence of the interaction of the Monogem ring with the ambient medium. The image shows a half-ring feature in the lowlatitude region, with its peak along the distorted boundary of the X-ray ring, where hot gas is in direct contact with the newly found Ha ring (the Gemini Ha ring) centered at (l, b) ∼ (191.5Њ, ϩ5.0Њ). Only a small portion of the X-ray ring is bright in C iv in the high-latitude region, where hot gas is seen to extend to a great distance from the ring. We have also detected other ionic emission lines in several regions of the Monogem ring, such as C iii l977, O vi ll1032, 1038, Si ii* l1533, He ii l1640, and O iii] l1666.

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