Direct transmission of data to Earth concluded in late 1977 because of budgetary considerations, but as the stations' lunar laser ranging corner-cube retroreflector arrays are passive instruments, they are still being used.
Transmisi data langsung ke Bumi di akhiri pada tahun 1977 karena pertimbangan anggaran, tetapi setelah stasiun rentang laser Bulan menjadi instrumen pasif, transmisi data masih terus dilakukan.