The PoGOLite flight did not turn out as we had hoped. A few hours after the spectacular launch at 2 AM on Thursday 7th July it became clear that the balloon’s altitude was lower than expected. It was soon after determined that the balloon was in fact leaking and that the altitude had started to steadily decrease. Since the balloon was approaching a mountainous region it was decided to terminate the flight – a 5 day flight to Canada was no longer an option. We were, of course, extremely disappointed and frustrated. During our few hours aloft we managed to commission the polarimeter and start pointing exercises with the attitude control system. The first guide stars we selected appeared nicely centred in our field-of-view and we were eagerly awaiting the Crab rising in a couple of hours time.
Before shutting down the instrument we did manage to point at Cygnus X-1 and take some data. The pointing worked beautifully, but we were already too low to allow meaningful X-ray observations. The gondola was finally cut from the balloon around 0730 on Thursday morning in the vicinity of Kebnekaise and landed by parachute near to Nikkaluokta. Initial GPS information indicated that it had splashed down in a lake, but fortunately this was not the case. We managed to locate the gondola the day after and were relieved to find it relatively intact.
So, what happens now? The first step is to understand the status of the polarimeter, attitude control system, star trackers and electronic control systems. Today we have made an initial appraisal and first results are promising. It will take more time to form a proper understanding of the situation however.
Given the excellent performance we experienced during our few hours aloft, we are keen to fly again as soon as possible!