The Collision Theory Until recently, the most widely accepted hypothesis for how the Moon was formed suggested that a Mars-sized object (sometimes called Theia) once collided with the still-developing Earth, about 20 to 100 million years after the Solar System first came together. While Earth appears to have come out of the collision fairly unscathed, the impact would have caused Theia's core and most of its mantle to sink into and merge with Earth's own core and mantle. Of the remaining dust and debris that were ejected into Earth's orbit, a small accretion disc was formed, and from this, our Moon eventually took shape. The consensus among scientists for almost five decades has been that Theia made a fairly low-energy graze across the surface of Earth. This hypothesis, known as 'the collision theory', went on to explain all kinds of other things - such as the large size of the Moon relative to Earth, and their separate rotation rates. Evidence that contradicts the collision theory: Another better theory that was done on of the highest resolution supercomputer is a theory that suggests that the moon was made in a few hours and not months or years. It starts with the collision of a Mars sized planet with Earth. Debris from the impact splits and forms two bodies. The smaller of the two will become the moon.The gravity of the larger body propels the smaller body forward and launches it onto a wide and stable orbit. This can explain why the. Moon is tilted. We need more lunar samples to be broyught back to earth to study from NASA'S future Artemis missions to figure out which of these two theories are correct. (OCT 04, 2022) (https://www.nasa.gov/solar-system/collision-may-have-formed-the-moon-in-mere-hours-simulations-reve al/) (https://www.youtube.com/watch?v=kRlhlCWplqk) A team from Washington University decided to study seven Moon rocks, collected from the old Apollo samples from the '70s, amd eight Earth rocks. The team found that every signle isotopic signature in the chemical analysis matched up to both Earth and the Moon except for one:heavy potassium isotope in the lunar samples. In order for this heavy-potassium isotope to appear separately in the lunar rocks, they must have sustained some incredibly hot temperatures, and from this, the team suggests that the Moon-forming collision was more violent than the Collision Theory states.As Loren Grush explains over at The Verge: "The collision that formed the Moon wasn't low energy at all, Wang argues. Instead, the impact was extremely violent, pulverising most of Earth and the impactor, and turning them into a vapour. In this scenario, the vaporised Earth and impactor mix together into a giant dense atmosphere. This atmosphere then cools and condenses into our planet and its satellite." (13 September 2016) (https://www.sciencealert.com/new-evidence-is-forcing-scientists-to-reconsider-how-the-moon-was-forme d) (https://www.theverge.com/2016/9/12/12879766/moon-planetary-collision-theory-earth-impact) Evidence for the collision theory: There is differnece between the elemental makeup of the Earth and Moon because the moon was different from the start. A scientist called Simon, Gargano et al decided to study the amount and type of chlroine in the moon rocks because chlroine is a volatile element, it vaporizes at a low temperature. The reseracher found teo isotopes of chlorine, a heavy one and a light one. He found that the moon's rocks had less light chlorine and more heavy chlorine than Earth. The Collision Theory proves this because the massive Earth would have easily attracted the light chlorine after colliding with Theia, while the less massive moon would have only been able to keep the heavier chlroine because it vaporized easier. (Sep 21 2020 • 3:22 PM) (https://nerdist.com/article/planet-collision-formed-the-moon-nasa-evidence/) Scientists widely agree that an ancient planet, called Theia, likely smashed into Earth as it was forming billions of years ago, making the moon, but nobody knows what happened to the remaining fragments of Theia. There are two massive, distinct blobs that are embedded deep within the Earth. The masses — called large low-velocity provinces, or LLVPs — were first detected in the 1980s. One lies beneath Africa and another below the Pacific Ocean. These blobs are thousands of kilometers wide and likely more dense with iron compared with the surrounding mantle, making them stand out when measured by seismic waves. But the origins of the blobs — each of which are larger than the moon — remain a mystery to scientists. Dr. Qian Yuan believes that these LLVPs are the remaining fragments of Theia. “I was afraid of turning to other people because I was afraid others would think I’m too crazy,” Yuan said. In that environment, if the material that makes up the LLVPs was too dense, it wouldn’t be able to pile up in the jagged formations that it appears in, Desch said. And if it were low enough in density, it would simply mix in with the churning mantle. The question was this: What would be the density of the material left behind by Theia? And could it match up with the density of the LLVPs? Researchers used higher-definition modeling with 100 to 1,000 times more resolution than their previous attempts, Yuan said. And still, the calculations lined up: If Theia were a certain size and consistency, and struck the Earth at a specific speed, the models showed it could, in fact, leave behind massive hunks of its guts within Earth’s mantle and also spawn the debris that would go on to create our moon. “That was very, very, so very exciting,” Yuan said. “That (modeling) hadn’t been done before.” (Updated 8:37 PM EDT, Fri November 3, 2023) (https://edition.cnn.com/2023/11/03/world/earth-moon-theia-collision-llvps-scn/index.html) In conclusion, I think that the collision theory is real, because its evidence is newer and done with more advanced technology.