M51- Cosmic Whirlpool

The Hubble Telescope took this image in 2005. The two galaxies are about 31 million light years apart but the smaller galaxy in the background is a satellite galaxy. What I find most interesting is the brihgter objects in the main galaxy. They seem too big to be a normal star, so a couple theories I came up with was that maybe they were galaxies behind the main one, super stars (a theory of the universe is that first there were super large stars that super nova'd and became galaxies, so I'm thinking maybe these are stars that are still breaking up and becoming smaller), or a suggestion of Mr. Percival's is that maybe they are star clusters. That's hard for me to imagine though since when we saw star clusters through the telescope they seemed to have no color, but that means nothing in astronomy.