Are the moons of jupiter visible through a pair of 10×50 binoculars?

I have been seeing 1 dot adjacent to jupiter with my 10x50 binoculars. Is it mere psychological effect or I have really seen a satellite. I believe I checked on K stars it shows Io has magnitude around 5 and Ganymede around 4...something.
One day I see the dot, the next day its gone. Then again after a few days I see the dot. May be it does not show up when the moon is bright.

Thanks for your time.