matter meets antimatter perhaps? Arent we supposed to see a second sun in the end of days?
Not speculation, it was confirmed quite a while ago. If I remember right, it was the first definite natural antimatter observed, and was how they determined what to look for to find antimatter plumes around black hole accretion disks.
But it's not significant amounts. Antimatter isn't that special unless you have a lot of it all at once in a non-vacuum. If you've ever had a PET scan, you've been bombarded by a beam of antimatter which was allowed to annihilate inside your body. If you gathered up the entire antimatter belt around the Earth and dropped it in somebody's lap, they'd probably still be able to have children. Even Jupiter's magnetic field doesn't trap enough antimatter to create a reaction that could be imaged.
Also, and more critically, Mercury doesn't have a magnetic field.