The object also appeared out of nowhere. It just wasn't there before. In fact, they don't even know where it is exactly located because it didn't behave like anything they know. Apparently, it can't be closer than 130 light-years but it can be as far as 11 billion light-years away. It's not in any known galaxy either. And they have ruled out a supernova too. It's something that they have never encountered before. In other words: they don't have a single clue about where or what the heck this thing is.
Your guess is as good as mine.