Trek's End by John Walker

File this short story under the category of "Unintended Consequences." It begins:

"I saw it happen. I witnessed the end of the world. And since I'm the only human who saw it, I'm going to write it down, even though there won't be any more generations of humans to read it. Somehow I need to. Perhaps another species will learn from our experience. Probably not. Certainly we never imagined how dangerous a galaxy we grew up in."

The story was published on Moon Day, 2003, on the author's web site.