Image noise is a random variation of brightness or color information produced by a photo film or digital sensor. Image noise is an undesirable by-product of photography and does not come from the actual objects in the picture.
Image noise can be in the salt-and-pepper type, forming bright dots in the dark parts of the image. When appearing in the dark part of the Moon, flat-Earthers incorrectly claim they are stars, “proving” that the Moon is transparent. In reality, these are just image noise, not part of the actual objects.