Armstrong's unrehearsed change of call sign from "Eagle" to "Tranquility Base" emphasized to listeners that landing was complete and successful.
ˈɑːɹmstɹɔŋz ˌʌnɹᵻhˈɜːst tʃˈeɪndʒ ʌv kˈɔːl sˈaɪn fɹʌm "ˈiːɡəl" tuː "tɹæŋkwˈɪlᵻɾi bˈeɪs" ˈɛmfɐsˌaɪzd tə lˈɪsənɚz ðæt lˈændɪŋ wʌz kəmplˈiːt ænd səksˈɛsfəl.