Strange stars on this image.

[Peco4321]

Took this last night with cannon 1100d with standard lens, 40 sec exposure f/5 ISO 1600 18mm focal length. 

There are lots of white star like dots on the image at the bottom and over the cottage. What could this be and what do o need to do to stop it happening again?  

[Nicho]

Hi Peter ,

Theses dots are where your camera is getting hot or (noise )which you can usually get rid of it with darks but as its a standalone picture i would use a Paintshop programme and use a clone tool to take them out.

Nick