Figuring out How to Deal with Cosmic Horror

From everything I've researched, they usually destroy everything in their path. There are plenty of stories of people running from them and barely surviving or seeing it from a perspective at a distance and not interfering. Which I understand you don't want to attract the attention of them. Cosmic Horrors are born from the negativity and feelings of mortals in the Outer Rims of the Astral Sea. It doesn't seem like there is any way to kill them, which is unfortunate as there isn't a permanent solution on how to get rid of these creatures. From what I've seen there are stories on putting these creatures to sleep with ancient rituals, none of these stories detail how as I don't think it's something that should be in the wrong hands. Which just makes it harder when you have to deal with one on your own, however there are connections and people that have the answers. My first thought was Professor Blackstone of Scrivining and Symbology who is known to have mastered the technique of permanency. He could do such a task but it would take away more magic than he could produce. Luckily we had a lecture speaker who had connections to the Conclave of Knowledge, I became an intern at this Conclave over the summer and I gained a lot of knowledge but most important how to put one to sleep. It's a very strong spell that is required and I don't think anyone could replicate it, however if this spell goes wrong while you are in the presence of this creature I assume it'll only piss it off and attract the attention of it due to the magic. Which means the person casting will need an escape plan or a way to deal with this creature, which presents another issue in itself on how to do this safely. I've been told there is a magical metal ship that floats through space, on my planet there isn't something like that. The idea is either get a ship that's fast enough and hidden enough to not attract the attention or to use magic to transport somewhere the Cosmic Horror couldn't follow. Which means we've reached another road block.