Plotted entries from OPSLOG files in MIDI report DELIN_TEMP, plot 1 (data set A1_GRISM_ops):
(DATE changes at 21:00 UT or MJD-OBS = xxx.875)
DATE       	MJD-OBS      	values
====================================================
2011-10-14	55849.333819	2339.144775
2011-10-16	55851.325856	2366.666748