Amy, Rory, and River talk at a diner when they discover the fourth envelope was sent to the Doctor, alive and 200 years younger than the one at the lake. The Doctor’s companions tell him about space 1969 and Canton, but refuse to tell him about his death or that the sender is the Doctor himself. The Doctor and his companions travel back to 8 April 1969, where the younger Canton, a former FBI operative, is briefed by President Richard Nixon about a series of phone calls Nixon received from a young girl asking for help. The Doctor arrives in Washington, DC and convinces Nixon to give him a few minutes to locate the girl. Based on the phone call and the girl’s mention of a “spaceman”, he tracks down the Florida intersection the girl where is located. Meanwhile, Amy meets and takes a photograph of one of the leaders of the Silence, a group she also saw by the lake which people forget about any time someone stops looking at them.
Titan has three large seas. However, the seas of Titan are not filled with water, but are filled instead with swirling liquid hydrocarbons. All three of Titan's exotic seas are close to its north pole, and they are surrounded by many smaller hydrocarbon-filled lakes in the northern hemisphere.
Similarly, in Norse mythology, Mani is the male personification of the Moon. Mani wanders across the sky in a horse and carriage, perpetually pursued by the Great Wolf Hati who catches him at Ragnarok--which is the "Twilight of the Gods," and the end of everything, in Norse mythology--that is, until it all begins anew.
In addition, the newly collected data derived from the GRAIL mission helps astronomers redefine the late heavy bombardment--a proposed episode that occurred about 4 billion years ago, during which a heavy shower of projectiles pelted the bodies of the inner Solar System, including Earth and its beloved Moon, creating heavy lunar cratering in the process. The concept of the late heavy bombardment is primarily based on the ages of massive near-side craters that are either within, or adjacent to, dark, lava-flooded basins (lunar maria), that are named Oceanus Procellarum and Mare Imbrium. However, the composition of the material existing on and below the surface of the lunar near-side indicates that the temperatures beneath this area are not representative of Earth's Moon as a whole at the time of the late heavy bombardment. The difference in the temperature profiles may have caused scientists to overestimate the amount of crater-excavating projectiles that characterized the late heavy bombardment. New studies by GRAIL scientists indicate that the size distribution of impact craters on the lunar far-side is a more accurate reflection of the crater-forming history of the inner Solar System than those pock-marking the near-side.