One of the crew's major tasks was reconnaissance of planned future landing sites on the Moon, especially one in Mare Tranquillitatis that was planned as the Apollo11 landing site.
wˈʌn ʌvðə kɹˈuːz mˈeɪdʒɚ tˈæsks wʌz ɹᵻkˈɑːnɪsəns ʌv plˈænd fjˈuːtʃɚ lˈændɪŋ sˈaɪts ɔnðə mˈuːn, ɪspˈɛʃəli wˈʌn ɪn mˈɛɹ tɹˌæŋkwɪlɪtˈɑːɾiz ðæt wʌz plˈænd æz ðɪ ɐpˈɑːloʊ ɪlˈɛvən lˈændɪŋ sˈaɪt.