As it explains, the mysterious 'radio circles' detected in outer space have no known cause. Most distant object in outer space that emit radio waves also emit other types of radiation of other wavelengths but not these objects which is part of why they are so strange. One of the problems in theorizing a possible cause is that we still not sure roughly about how far they are away they are as their approximate distance away is currently very hard to determine.
There is a pretty wild theory mentioned in this video that they are the sign of the entry-exit points to huge space worm holes! I would find it nice if that theory proves correct but somehow I think its unlikely but, who knows!
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@humy
"... I think its unlikely but, who knows! "
I agree. Dr. Who is probably the only one that knows.