MASS teaches us about the YES2 Big Bang

With Casi and Aage we are looking at the MASS data now. This system was added as a bonus in a 2 week crash effort before satellite completion to get some science out of the MASS subsatellite (its main purpose was to secure and release Fotino). So we cannot be very demanding on its results. We thus far are only able to decode data for the first 150 meters or so. Nevertheless, being the event just after the Grand Ejection of MASS/Fotino from FLOYD, this is significant information. It is a bit like the observable horizon of the Big Bang. With this data we have captured the following events that like in the Big Bang can be propagated according to better understood laws ;)

• ejection and induced pitch-off rate
• oscillation/rotation of MASS/Fotino after ejection
• correct start of timer for MFD release
• tension at zero turns and response to barberpole turning
• tie-downs, kevlar and ripstitch behavior at zero turn

The status bits from MASS telemetry are indicating that the MFD circuitry was powered, MFD was not fired (good thing) in the first 60 seconds and the ejection was properly measured.

The gyroscopes show the above (unscaled, time accurate within 1 second) results, indicating a slow oscillation (30 second), consistent with a nominal pitch-off rate of several degrees per second (TBC). Some initial effects can be seen, that may be related to the tether tie-downs breaking (they are expected to reduce the rate by some percentage), expected after 0, 0.3 and 2 seconds. The irregular behavior around 10 seconds is quite possibly related to the tension transition after ripstitch deployment to low tension and then the barberpole turning up (the feedback starts to turn the pole at 8 seconds), thereby increasing tension, affecting the oscillation once more (see correlation with tension plot in more recent Blog entry). The ejection simulation parameters will be tuned to reconstruct the details of those first critical seconds of YES2, that seem to have passed neatly for the subsatellite.