1. Közösség
2. General Khan Academy Questions
3. what are the black hole badges

Yeah, I don't thing that anyone knows how to get the black hole badges except for the staff. You can, however, find a bunch of rumors floating around the internet. Good Luck! B-)

1. Közösség
2. General Khan Academy Questions
3. How do you thank someone when they comment on a question I've asked?

Or, you could like/up-vote their comment!