if (n_elements(fem) eq 0) then rd_fem,'1-sep-91',!stime,fem
;
utplot, fem, fem.night/60, /ynoz, ytit='S/C Day Duration (Min)'
pause
utplot, fem, fem.night/60, ytit='S/C Day Duration (Min)'
pause
;
dx = deriv_arr(int2secarr(fem))/60.
utplot, fem, dx, /ynoz, ytit='Minutes between S/C Days

;
end