City-d asteroids smacked ancient Earth 10 times more often than thought

My observation. Reports of more catastrophism in Earth's past here, this report focused on 3.5 to 2.5 billion years ago in the Precambrian, and perhaps 10x larger impact rate wreaking havoc on life and possible oxygen levels too during the Precambrian. Then there are the 10 mass extinctions reported in the past 260 million years according to other reports along with the five major mass extinctions in the fossil record documented since the Cambrian explosion fossils. The early solar nebula and accretion disk with many planetesimals and small bodies colliding like Theia to make the Moon shows widespread catastrophism used in science now to explain our origins and life on Earth today. 3 billion years ago, the Earth's LOD is much shorter than present 24-hour day and the Moon orbits much closer to Earth too. Perhaps <= 42 earth radii compared to mean today near 60.3 earth radii and lunar month <=16 days. A quite different Earth LOD, lunar orbit, and lunar month featuring more impacts during the Precambrian leading to more catastrophism during the evolution of life into the more complex life forms that are said to appear later in the fossil record. And then the Cambrian explosion fossils on to present, even more mass extinctions and 10 others in the past 260 million years ago. Catastrophism operating violently, including when abiogenesis is assumed to create life on Earth and possibly other bodies like Venus, Mars, Europa, and Enceladus in the solar system. Quite a catastrophic mix presented now to explain our origins and evolutionary tree of life in the fossil record 😊.
 
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The postulated LHB takes place earlier than this time period covered in the article, thus the evolution of life on Earth is well underway now with this article catastrophism presented. LHB is undergoing an evolutionary change too, some are now calling into question, I will wait and see. Meteorite study calls into doubt a popular theory about the early solar system, https://phys.org/news/2020-09-meteorite-popular-theory-early-solar.html, Sep-2020.

Lunar sample tells ancient story through international collaborative effort, https://phys.org/news/2021-06-lunar-sample-ancient-story-international.html, June-2021. Ref - Lunar samples record an impact 4.2 billion years ago that may have formed the Serenitatis Basin, https://www.nature.com/articles/s43247-021-00181-z, 09-June-2021. “Introduction One of the outstanding questions in planetary science is the exact timing and duration of impact bombardment to the inner Solar System, including the purported Late Heavy Bombardment (LHB)1,2,3,4,5,6,7,8,9,10,11. Direct constraints on the timing and duration of the impact bombardment can be provided by absolute ages of the most ancient lunar surfaces and basins7."

By finding more impact related events in the period 3.5 to 2.5 billion years ago (after the postulated LHB), extinction events could take place too. Thus abiogenesis may have to start over again, perhaps on a repeated basis to allow the evolutionary chain for life on Earth to *advance* or so this connection could be made :)
 
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I believe that the current number for our solar system to make one orbit around the galaxy center is 226 million years. Could the 10 mass extinctions reported for the last 260 million years be a function of our solar system passing through a particular portion of our orbit around the galaxy center? Could we be in for a series of potentially Earth crossing asteroids? (for which we seem marginally prepared, albeit the Chinese recently announced plans for an aggressive response to such)..
 
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This increase in impacts would seem to push life formation and development back perhaps a billion years. If so, the Fermi Paradox makes lack of alien evidence even more complexing as they may have had development much sooner than we had.

Alternatively, such things may prove necessary for achieving inelligent life forms. Killing-off dinosaurs may have only been one big benefit from one huge impact. This too might limit the chances for distant neighbors if more odd things are needed.

Passing stars can trigger infalling events from the Oort, but it’s unlikely these stars were very close else we would see greater eccentric orbits for our planets.
 

Catastrophe

"There never was a good war, or a bad peace."
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After reading the references in Cat's post #7, I'm going to curb my enthusiasm for any near in viewing of Betelgeuse going supernova. Perhaps our solar system should put a few more ly between us and Betelgeuse before the big event happens just to insure that the term "crispy" refers only to high cholesterol food.
 
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Indeed, smack down and impact events are required and much catastrophism to explain the origin of Earth's water today along with the smack down record in the fossil record :). I was reading this from a source (July 2020 publication) I use on how many meteorites are required to deliver Earth's water supply. Something I do not find commonly reported to the public.

"According to the Smithsonian, the water came to Earth via comets and asteroids (the latter become classified as meteorites upon hitting the earth) in a symphony of choreographed hits. And “such bodies (probably more asteroids than comets) could easily have delivered oceans’ worth of water.”1 The Smithsonian simply declares that these cosmic agents provide the easy answer to this seemingly difficult question. And then as a concluding touch, “so, the next time you turn on the tap, think of the flowing water’s long and wonderful journey.”1 Trillions are required! Is this seemingly simple explanation really possible? How big would these cosmic visitors have to be? And how many direct hits to Earth would it actually take to “easily deliver an oceans’ worth of water”?...The starting point for these calculations begins by establishing how much water is actually on the earth. Based on the surface area of water on Earth and its average depth, a conservative estimate is about 1.386 × 10^21 litres or 1.386 billion cubic km^3.2 This number is staggering in itself. The large supertankers used to transport massive amounts of liquids (usually crude oil), can hold on average about 125 million litres (33 million US gallons).3 If the average amount of water4 were a very generous 10% on every water-containing meteorite, and every meteorite were 10 times the size of a supertanker, a minimum number of 11.1 trillion meteorites would be required for this delivery service!"

1. Greene, B., How did water come to Earth? It took an out-of-this-world arrival to get that perfect chemical combination for water to fill our planet, smithsonianmag.com, May 2013.
2. How much water is there on Earth, usgs.gov, accessed 14 Aug 2019.
3. Tanker Sizes and Classes, transportgeography.org, accessed 24 Jul 2019.

Yes indeed, smack down and impact catastrophism is required to explain our origins today, including Earth's water supply :)
 
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