The basic idea of the site is for users to create a character and create art and / or a background story to go with the article, as mentioned in the introduction a combination of art and back story is not essential; a member can upload an image with a headline and challenge others to write the background story or you may wish to publish a story and one of the artists among us can create an image(s) to go with the story.
As for your character, they can be whatever you like as long as they fit in with the various canons as described in the "Tour" section of the site.
The same is true for any news, it should fit within the timeline and current state of the universe which can also be found in the "Tour" section of the site.
We must stress though that not all of the universe is "set in stone", which means that over time as new content is added by users, the SCM universe can evolve, with new antagonists and allies.
Perhaps you would like to pick one of the planets and make it your own by becoming the Governor or have your character aboard one of the many vessels, or in one of the services. You may even be an anarchist and submit antiestablishment material.
The bottom line:
You are free to publish what you like as long as it fits within the universe and it is not X-rated (R-rated or implied Sexual, Violence or Drug related articles are fine). We also encourage humour in submissions, if that is "your thing".
Any questions? - ask in the forums and we can help out.
We look forward to working with you.