The week before Q said that NASA announced they developed an AI capable of mapping the universe. They've only used used the AI to go through 2% of keplers data so far.
I don't think the public knows how close the closest star is. Most of the public doesn't even know there's probably a 9th star in our universe.
The sumerians said there was 9th star stuck in a orbit between our sun and its original star. I think that's most likely the closest star.
You can read about the AI on NASAs website and the 9th planet on space.com.
I fully expect in the next year or so to get some answers from NASA.