The study of albedos, their dependence on wavelength, lighting angle ("phase angle"), and variation in time composes a major part of the astronomical field of photometry.
ðə stˈʌdi ʌv ælbˈiːdoʊz, ðɛɹ dᵻpˈɛndəns ˌɔn wˈeɪvlɛŋθ, lˈaɪɾɪŋ ˈæŋɡəl"fˈeɪz ˈæŋɡəl", ænd vˌɛɹɪˈeɪʃən ɪn tˈaɪm kəmpˈoʊzᵻz ɐ mˈeɪdʒɚ pˈɑːɹt ʌvðɪ ɐstɹənˈɑːmɪkəl fˈiːld ʌv foʊtˈɑːmətɹi.