This is the longitude of the telescope, measured in decimal degrees. The usual convention of + for north and - for south of the Equator should be observed. The same accuracy is required as for longitudes, so you should supply an accurate value.
| Column Label | Contents | Units | Variable Type | Format |
| TELESCOP | focus name | C*6 string | A8 | |
| DIAM | diameter | meters | R*4 real | F7.3 |
| LON | longitude | degrees | R*4 real | s12.5 |
| LAT | latitude | degrees | R*4 real | s11.5 |
| HEIGHT | height | meters | R*4 real | F6.0 |
| TUBETYPE | tube type | C*6 string | A8 | |
| TUBEDIAM | tube diameter | meters | R*4 real | F8.3 |
| TUBELEN | tube length | meters | R*4 real | F7.3 |
| DOMETYPE | enclosure type | C*4 string | A8 | |
| DOMEDIAM | dome diameter | meters | R*4 real | F8.2 |
| SLITWID | slit width | meters | R*4 real | F7.2 |