The Six Body Problem

 So, this one is kind of fun. TOI-178 has six planets (that we know of), and five of them are in an orbital resonance chain.

Which, by the way, shouldn't be happening, especially as they're all different sizes and compositions. There's a super-Earth hanging out right next to a Neptune-type ice giant.

Oh, and planet 3 is less dense than planets 4 and 5.

Which also shouldn't be happening.

Aliens? Nah...but something strange is going on here. Also making a mental note because something just clicked in my brain.