Второе, почти наверняка.
http://www.childrenofthemanhattanproject.org/MP_Misc/atomic_timeline_3.htm
August 8, 1945 -
At Foreign Minister Togo's request Ambassador Sato tries to persuade the Soviets to mediate surrender negotiations. Molotov cancel's the meeting, then announces that the Soviet Union is at war with Japan effective the next day.
Leaflet dropping, and warnings to Japan by Radio Saipan begin (Nagasaki does not receive warning leaflets until August 10).
Fat Man unit F33 is dropped in practice bomb run.
Assembly of Fat Man unit F31 with the plutonium core completed in the early morning.
2200, Fat Man is loaded on B-29 "Bock's Car".
August 9, 1945 -
0347, Bock's Car takes off from Tinian, the target of choice is Kokura Arsenal. Charles Sweeney is pilot. Soon after takeoff he discovers that the fuel system will not pump from the 600 gallon reserve tank.
1044, Bock's Car arrives at Kokura but finds it covered by haze, the aimpoint cannot be seen. Flak and fighters appear, forcing the plane to stop searching for it. Sweeney turns toward Nagasaki, the only secondary target in range.
Upon arriving at Nagasaki, Bock's Car has enough fuel for only one pass over the city even with an emergency landing at Okinawa. Nagasaki is covered with clouds, but one gap allows a drop several miles from the intended aimpoint.
11:02 (Nagasaki time) Fat Man explodes at 1950 feet near the perimeter of the city, scoring a direct hit on the Mitsubishi Steel and Arms Works. Yield is 19-23 Kt (best estimate is 21 Kt).
Oppenheimer cable Groves with the following shipping schedule: 11 Aug. first quality HE unit; 12 Aug. next plutonium core; 14 Aug. another first quality HE unit.
