The region is relative far from larger cities, so I wouldn't expect many bombs to be there. While there are still plenty of bombs being found in Germany, most of them are in the city centers as bombing was concentrated there.
Well, sure. But the allies bombed just about anywhere for any reason. I'm sure there are many remote fields which could have been holding areas for things that would have made good targets. And if a bomb missed a convoy on either side of a road, it could sink waaaay into a mud bog, not go off and barely leave a trace behind. If that "road" was a temporary detour through farmland for a few months in 1941? Yikes!
I don't know anything about the chemistry of explosives but if those bombs didn't explode for 80 years are they going to explode now? Furthermore they are a problem if they build on them. If one explodes away from the telescope they lose minutes of data, probably not a big deal.
Yes, unfortunately, there is still a risk. Just a few months ago a bomb was set off in the center of Munich at the train station during construction work.
That seem to be a failure of a certain brand analogue computer used for precision bombing at that time. They have to switch to carpet bombing. Still would they just bomb a field I wonder even carpet bombing.
