Distracted by thinking about Rufus and his mine, Dinah became aware that the Space Troll’s transmission had changed. Instead of the familiar QRA QET, it now began with QSO, which in this context meant "can you communicate with... ?" This was followed by an unfamiliar call sign, which she didn’t recognize as such because it was so long: a string of digits and letters that didn’t follow any of the standard conventions for radio call signs.