Physical Nature of the [S II]-Bright Shell Nebulae N70 and N185

Ning-Xiao Zhang, You-Hua Chu, R. M. Williams +3

N70 and N185 are two large ($\ge$100 pc in diameter) shell nebulae in the Large Magellanic Cloud (LMC). Their high [\ion{S}{2}]/H$\alpha$ ratios rival those of supernova remnants (SNRs)…