This text file simply describes the columns of the table, and gives some background information about it.
Successive columns list the calendar date of the observation as year, month, and day.
The next entry is the Julian date, with the initial digits 24 deleted. Thus the full Julian date of the first observation is 2,444,193.9. To hopefully clarify, I will give as an example a reading of the first line. An observation was made on 16 Nov 1979, which is Julian date 2444193.9. The observation was made by me at the F. L. Whipple Observatory on Mt Hopkins.