Launch managers say weather remains the chief concern as preparations continue towards the delayed launch of Ares I-X at Kennedy Space Center. Lightning strikes around Pad 39B during the night forced several system re-tests which led to the launch attempt being put back to at least 9 a.m. eastern. The familiar weather issue that forced the launch attempt to be scrubbed yesterday, then became the dominant concern and NASA is currently holding the countdown at T-4 mins, waiting for a suitable window to appear.

The nearest lightning strike was around 700 yards from the vehicle, and had a field strength of around 20% the energy levels that would “cause concern” say officials. One of the major systems which could have been impacted by the high radiated field is the thrust vector control (TVC) – a vital system in the Ares I-X which is designed to conduct a fairly intense roll maneuver shortly after clearing the tower. However the final check of the TVC will not be possible until after the start of the auxiliary power unit, at around T -28 sec. At this point the launch sequence will automatically stop if an error is detected, say managers. So for the moment, it’s all eyes back to the skies while we wait for a possible launch in the next hour.