How I explain stuff

Occasionally, my girlfriend asks me what I'm reading. She's not particularly science minded so I have to break it down a lot. The other day, she asked me what the article I was reading for a recent UT post.

Here's how I explained it:

So there's a little star and a big star. The big star starts throwing stuff everywhere and the little star goes nom nom nom. If it noms too much, it explodes. But sometimes it throws up what it nommed. They want to know if its ever going to nom enough to explode or if it keeps throwing up so much it never gets there.

Can you figure out what the topic was before you read the UT post?