How to deal with my childs?

teacher who has mademy little girl feel really small. My little one went to school today all exited about an astronomy study she had worked on herself for her own interest. she was so happy to tell the teacher about how she saw a star called betelguise and went on to describe it. only to be dismissed by the teacher and told you couldnt see it without a telescope and not to be silly.... im fuming.... not only as this teacher got it wrong on more than one occasion....its knocked my kids confidence when she was ridiculed in front of her cl...hel;p please....shall i make a complaint about her