I like this. Just how big is a Universe anyway? The thought is very comforting.

Some are right here on Earth already.

Sounds like they are more 'lifelike' than a virus. A virus can't reproduce on it's own, and is created as a complete unit, that repeats reproduction with host DNA. We don't have much doubt what it consists of and the problem arises with our insistence on classification - Where do we put it, and why ? If it performs the functions of life, then perhaps we have to do work on our definition of organic. Perhaps with the qualification that life on earth is organic, we might just leave the question open, without pretending we think we know what we'll find. There likely to be ways life exists, that will show us how small our reality is.

seems the Universe is quite big -))

and we probably have such a tendency 2look for a lost coin only under the nearest lamp !!