The two small spacecraft GRAIL A (Ebb) and GRAIL B (Flow) were launched on 10 September 2011 aboard a single launch vehicle: the most-powerful configuration of a Delta II, the 7920H-10.
Dua pesawat ruang angkasa kecil GRAIL A (Ebb) dan GRAIL B (Arus) diluncurkan pada 10 September 2011 di atas kapal kendaraan peluncuran tunggal: konfigurasi paling-kuat dari Delta II, 7920H-10.