streaks of light ?

[ultramol]

Hi all, I have used my telescope quite a few times since I got it and all seemed well, but the other night when I observed the moon or a very bright star there seemed to be two opposite thick beams of light coming from them. Does anyone know what may cause this to happen ?

[DrRobin]

If they were at 90 degrees to each other then they are diffraction spikes caused by the secondary holder vanes.  All newts have them.

Robin

[ultramol]

Thanks Robin, these though even on the moon are almost as wide as the moon and shoot out 180 degrees  and go off the FOV. I have just thought though it was a very wet night dew wise . Could it have been dew on the mirrors ?