Very cool! So, ok, the first thing that occurs to me is ... how hard does that capsule come down? -XC PS - In summer it would have flown higher and faster, natch. So even harder to track. PPS - Do you have to warn anyone that you're putting a balloon into a flight path?
1) Not very fast. We had an 8' nylon parachute, which, according to the manufacturer, should have had a terminal velocity of ~10ft/s with our payload size (approx 7lbs). 2) Actually, the summer jet stream is much calmer, with predicted flight range less than half of that in the winter. 3) You do not, so long as its a small (I think below 12lbs) payload. You cannot, however, launch it within 5 miles of an airport. As far as I could find, there has never been an FAA reported case of a plane colliding with a weather balloon. 4) I have no idea if there are regulations on putting live invertebrates inside the payload...I didn't really want to find out either.