We confess to our use of an attention-getting blog title. Instead of “Four Theories of Moon Formation” we believe our chosen title engages readers with the currently best explanation of how Earth’s Moon was formed. This is known as the giant impact hypothesis. Some may object to our discussion with the rejoinder that the Moon was created six to ten thousand years ago along with the universe and all its living things. Our blog position has been to affirm credible evidence from science that our universe’s age is 13.73 billion years. Earth’s age is 4.6 billion years as a solid body followed by the Moon at 4.5 billion years. We enthusiastically endorse the biblical view that God created all things that exist in the beginning.
Before discussing the specifics of the favored theory of Moon formation, we review our position concerning God’s creative processes in this universe. In the beginning, God brought into existence the time, space, energy, and matter dimensions of the universe. Even atheistic and agnostic scientists acknowledge that the universe had a beginning. Logically, this points to the work of a Beginner. Believers in the account of Scripture believe the Beginner was the God of Scripture. The universe began 13.73 billion years ago in primordial time. We refer to the original cosmic event commonly known as The Big Bang. From this event sprang events of incredible fine tuning over intervening eons of time. This included formation of galaxies of stars with planetary systems such as our Solar System. Thus, the Big Bang was not destructive in the least. It was the beginning of fine tuned constructive processes sustained by the Creator who initially set the universe in motion.
Over 9 billion years of time elapsed from the cosmic beginning to the formation of our Solar System 4.6 billion years ago. The Creator of Scripture, unshackled from the constraints of time, was watching over the formation of our unique Solar System. No other planetary system among the millions formed in our universe possesses the qualities of our Solar System. In particular, Earth is unique in many hundreds of parameters which must be present and finely tuned to an incredible degree for life to exist.
One of the hundreds of fine tuning events was the formation of Earth’s Moon shortly after our planet formed as a solid body. The “cosmic crash” may remind some readers of science fiction. But as time goes on and discoveries multiply, the “fiction” appears more and more like a real event. About 4.5 billion years ago Earth was impacted by an indirect hit by a Mars-sized object called Theia. This impact released enormous energy and probably melted both bodies. Much of the material remained in orbit around Earth and later coalesced into a solid body—the Moon.
In the billions of years since the impact of Theia formed our neighboring satellite, the Moon has experienced many impacts with large bodies. These asteroids or comets left thousands of significant craters of various sizes, most of which have remained visible on the lunar surface. Some of these objects caused the Moon’s surface to melt and triggered lunar volcanoes. The bombardments of asteroids on the Moon and Earth have virtually ceased, but their impact craters bear testimony to the history of the Moon and its advanced geologic age. Atmospheric weathering factors have obliterated most impact features from Earth, but they remain on the Moon as geological birthmarks.
The giant impact hypothesis is a fairly recent discovery of astronomical researchers. Previous hypotheses included the capture theory posing that Earth’s gravity “captured” the Moon. Other theories included the accretion theory similar to the formation of discs of planetary material around a central body and the fission theory in which the moon was torn from the Earth’s Pacific basin.
Creationist Hugh Ross has written that our post title’s violent cosmic crash was really “The Perfect Collision” and far from a tragedy. On the contrary, the series of events may be considered part of the Creator’s fine tuning of our planet prepared to receive His ultimate creation—humanity in His image. In the 2006 volume Creation as Science, Ross says, “The collision that led to the formation of a just-right moon appears to have been perfectly aimed, weighed, and timed to change Earth from a “formless and empty” wasteland into a site where advanced life could survive and thrive. The degree of ‘anthropic’ fine-tuning manifested in just this one event argues powerfully for a divine Creator.”
In a broader vision, the giant impactor hypothesis could illustrate how most events in our universe have unfolded since the supernatural initial creation event. It could also instruct us concerning the difference between primary and secondary causation as God has authored the workings of our universe. Primary causation may be illustrated by the biblical statement, “In the beginning, God created the heavens and the earth.” “Heavens and the earth” could be translated “all that exists.” Secondary causation is illustrated by most (but not all) effects we observe in our world, including the purposeful formation of Earth’s Moon.
We close with a brief quote from our post of 8/26/15: “Our lunar companion is vital for life on Planet Earth.” In this quote is hidden the invitation to pursue careful research to discover how vital our lunar companion really is.