OK, what about if we just want to know what sort of data is in the FITs file, and not all of the information in the header? Again click on the data set gx301-2.lc to select it. Click on Column List in the File Utilities folder and click "run". A parameter box will appear. The free parameters for the working directory and data file name should be all filled in. Now click on "run" and an output box will appear with three columns. Make sure you scroll up so that the entire list of columns is visible. In the left column is the data variable name, in the middle is the variable type ("I" for integer, "E" for a real number in scientific notation, etc.), and the last column gives the units of the data contained in that column. Each row in the Column List output corresponds to a column in the data file. All of the columns are important for some scientific studies, but there are many more columns of data than are needed for these exercises!
Using the output from Column List answer the following questions (remember to scroll up to the top of the output window to see the entire output!):
- How many columns of data are there in this data set?
- Can you guess, from the variable names (in capital letters, on the far left) and the units, what the 1st, 2nd, 3rd and 8th columns measure? Note which of these columns would be used to make a lightcurve from this data and write down the capitalized variable names (you will need them soon).
- What units are used for these variables?