Order-sorting image_Mrk 421_obsid_21827 Dispersion coordinates field image_Mrk 421_obsid_21827 Sky field image_Mrk 421_obsid_21827 Source region detail images_Mrk 421_obsid_21827 Light curve_Mrk 421_obsid_21827 Flux spectrum (1)_Mrk 421_obsid_21827 Flux spectrum (2)_Mrk 421_obsid_21827 Counts spectrum_Mrk 421_obsid_21827 Flux Preview_Mrk 421_obsid_21827