Spatial Phenomenon chances?

[Felderburg]

I wanted to know what the cool diagram looked like for a spatial phenomena, so I generated some sectors. I have generated dozens in the general Expanse, and so far, not one has had a spatial phenomenon. There have been a few brown dwarfs, but no nebula, storms, waves, or anything liuke that. It doesn't look like anything's wrong in the generator's code to me, but I don't know. I guess it's a 20 after a 20 that results in one, so very low chances... perhaps an option to boost the chances would be neat? Just seems like there should be more non-star stuff in sector generation than the tables appear to give.

Edit: Using https://www.omnicalculator.com/statistics/dice it's a .0025 probability. Which is indeed very low. Possibly too low?