Looks like an asteroid ring to me - I've seen these that far away from a planet before. Check the system map - It'll tell you more about the rings if they are in fact there.
I'll have to concur with the above posts. If it is a ring, please post the system details and name! Would love to see that myself! Theres also a thread (Link) that has a bunch of interesting and weird systems and planets. A lot are the ring systems with major gaps.