Hear me out. First of all, Raxxla is a planet but the Omphalos Rift is the "artifact" that has the power. According to ancient mythologie, it is said to be in the center of the world (they believed the earth was flat). Now why do I think it's there? First of all, the center of elite dangerous would be that system. It's the most important system in the galaxy to pilots. Also to get to that system you need to be elite. Now I found something very interesting in an elite dangerous book.
You need to have elite to be able to visit the system. Also Lore-wise, if Raxxla was found already. It's not that they won't do anything to keep it secure. Makes sense right?
Now besides all that and this theory making sence to ancient mythologie, I have another lead.
I myself no not have the rank of elite, but I ask others to seek out this signal and find it's origin. Besides FD said they made Raxxla's location a tiny bit obvious.