Travelling south on rte 3a in Litchfield NH after dining out in BedfordNH wmy wife and I were about to take the left turn for Hillcrest road in Litchfield toward our home in Londonderry, when my wife yelled to me "what is that?!" I looked up to see a large glowing green spherical object on an east to west trajectory moving at what appeared to be a low arching altitude across the sky. When the object got even with my view of the road I was on it just went dark and dissappeared. I hesitated in order for us to see if there would be some explosion of to the west toward the city of Nashua or over the Merrimack river but I did not see any and then went home and reported what we saw to the Litchfield police. there was another vehicle behind me that must have seen this event but I did not stop as we were both shook up a bit by what we witnessed.