So now that you've learned all about big black holes, and small black holes, and social black holes, and not-so-social ones, you're probably wondering, "What's left?" Well, while we've talked a lot about COMMON black hole situations, there are always records to be broken! For example, the biggest black hole we know of is truly massive, being 40 billion times the mass of the Sun, and the smallest one could be only two and a half times the Sun’s mass. There's even a “spinniest” black hole that spins at over 1,000 times per second. Adorable! Next, depending on what planet you're from, there are also "closest" and "farthest" to think about. For example, if you live on Earth, the closest known black hole is about 3,000 light-years away. On the other hand, the farthest known black hole is about 13 billion light years away. Although, um, what that really means is that light from near that black hole took 13 billion years to reach us, and because the universe is constantly expanding ... that means now it’s ... um … well, it, um ... In any case, it’s still "farthest known." Let's move on! If you're feeling more adventurous, there are also some rarer black holes to be found – assuming some of them even exist, that is! For example, while we do know about small and big black holes, we’ve only found a few that that fit ... somewhere in between. It's also possible that tiny black holes may have formed back at the beginning of the universe when everything was just really packed together. However, even if they did exist, we definitely haven’t detected them yet. And finally, we'd love to catch two giant black holes crashing into each other because, well, we just haven’t seen that yet! So, if extreme adventures and rare finds are on the top of your black hole-watching list, grab your rocket ship – or your favorite observatory ­ and start searching!