One of the major sources of background are flashing satellites.
They can reflect the sunlight and cause a short flash, like the one
we expect from GRB.
Satellite tracks crossing our field of view over one night
are shown below.
The diagram is drawn by SkyMap
program
using MMCCANTS
data base containing 1600 satellites.
A spectacular example of 4m flash is shown below, as observed by two cameras
14 March 2004, 2:51 local time (GMT+1).
The sky was covered by a thin cirrus, hence our limiting magnitude is only about 8m.
| frame 1 | frame 2 | frame 3 | |
| K1 cam |  |
 |
 |
| K2 cam |  |
 |
 |
The flash can be easily attributed to one of the satellites
shown in the map (look at "02:51" time stamp).
A positive side of the flashing satellites is that they stand
as a test tool for our apparatus and flash recognition algorithms.
More information about tracking satellites can be found at: