SGF observations vary in return energy during a pass
due to sky
conditions and other factors. To maintain a single photon level
of return, ND filters from 0.0 - 4.0 are used in front of the
detector. Hence, a higher level of return energy needs a higher
ND filter grade.
Does this level of ND filter usage vary across the sky in azimuth
and elevation? Below are eight plots, each containg a sky plots
for Lageos 1, Lageos 2, Ajisai, Starlette, Stella and HEO satellites.
The plots are for the Hz and kHz systems in the daytime and at
night. The left handside set are all passes plotted with ND
variation in colour. The right hand side set is the same data
averaged on a grid.
These plots are updated regularly and contain data collected from May
2009 to present. |
|
ND
Filters plotted pass by pass |
ND
Filters plotted on an averaged grid |
| 10
Hz laser system in the day |
 |
 |
| 10
Hz laser system at night |
 |
 |
| kHz
laser system in the day |
 |
 |
| kHz
laser system at night |
 |
 |
