In September 2015, a new study provided an important missing piece to the intriguing puzzle of how our Moon came to be the lovely object that we see today.
Dr. Jason Soderblom said in a September 10, 2015 Massachusetts Institute of Technology (MIT) Press Release that the evolution of lunar porosity can provide scientists with valuable clues to some of the most ancient life-supporting processes occurring in our Solar System. Dr. Soderblom is a planetary research scientist in MIT's Department of Earth, Atmospheric and Planetary Sciences in Cambridge, Massachusetts.
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.