The largest, shining object in Earth's starlit night sky, our Moon has long been the source of mystery, myth, and poetry--a captivating inspiration for those who stare at the sky in wonder. But Earth's Moon is a very real object--the only body beyond our own planet that we have actually set foot upon, leaving our lingering footprints in its distant, alien dust. Earth's Moon has been with us almost from the very beginning, and even though it is our planet's closest companion in space, it has nonetheless managed to keep some of its ancient secrets very well. In September 2015, astronomers released a new study that shed light on Earth's bewitching companion's ancient and secretive past. Although our Moon now appears to be unchanging, as if it has always been exactly the same as it appears now--going through its beautiful and, yet, familiar phases, and controlling our ocean tides--in the distant past, things were actually very different.
Christian folklore claims the Man in the Moon is Cain, the eternal Wanderer, doomed forever to circle the Earth. In addition, there is a Talmudic tradition that says it is the face of Jacob etched out on the gleaming lunar disk.
"Impact simulations indicate that impacts into a hot, thin crust representative of the early Moon's near-side hemisphere would have produced basins with as much as twice the diameter as similar impacts into cooler crust, which is indicative of early conditions on the Moon's far-side hemisphere," noted lead study author Dr. Katarina Milijkovic in the November 7, 2013 JPL Press Release. Dr. Milijkovic is of the Institut de Physique du Globe de Paris.